I
The regulations governing tuition status at the time petitioners were enrolled in the Law School established certain requirements for eligibility for in-state tuition. To be eligible, a prospective student (1) must have lived in this state, (2) with intent to make it a home, (3) for at least six months, and (4) without being enrolled in an institution of higher education during the six-month period. Thus, to qualify for in-state tuition, the regulations required that the student be domiciled in this state and in addition have been so domiciled without being enrolled in an institution of higher education for at least the six months preceding the date of first enrollment or re-enrollment in such institution. For full discussion of domicile, see Hall v. Board of Elections, 280 N.C. 600, 187 S.E. 2d 52 (1972).
Petitioners do not contest the validity of Eegulation No. 1, which provides that “[t]he tuition charge for legal residents of North Carolina is less than for nonresidents” and that “[t]o qualify for in-state tuition, a legal resident must have maintained his domicile in North Carolina for at least the six months preceding the date of first enrollment or re-enrollment in an institution of higher education in this State.” (Our italics.) The State’s right to charge nonresidents higher tuition than residents is not challenged and has been repeatedly upheld as reasonably related to the State’s legitimate interest in operating, maintaining and financing its educational institutions. Johns v. Redeker, 406 F. 2d 878 (8th Cir.), cert. den. sub nom. Twist v. Redeker, 396 U.S. 853, 24 L.Ed. 2d 102, 90 S.Ct. 113 (1969). See also, Bryan v. Regents of University of California, 188 Cal. 559, 205 P. 1071 (1922); Landwehr v. Regents of University of Colorado, 156 Colo. 1, 396 P. 2d 451 (1964); Clarke v. Redeker, 259 F. Supp. 117 (S.D. Iowa 1966); Clarke v. Redeker, 406 F. 2d 883 (8th Cir.), cert. den. 396 U.S. 862, 24 L.Ed. 2d 115, 90 S.Ct. 135 (1969); Kirk v. Board of Regents of Univ. of California, 273 Cal. App. 2d 430, 78 Cal. Rptr. 260 (1st Dist. Ct. App. 1969), app. dism. 396 U.S. 554, 24 *636L.Ed. 2d 747, 90 S.Ct. 754 (1970); Starns v. Malkerson, 326 F. Supp. 234 (D. Minn. 1970), aff’d without opinion, 401 U.S. 985, 28 L.Ed. 2d 527, 91 S.Ct. 1231 (1971); Thompson v. Board of Regents of University of Neb., 187 Neb. 252, 188 N.W. 2d 840 (1971); Spencer, “The Legal Aspects of the Nonresident Tuition Fee,” 6 Ore. L. Rev. 332 (1927) ; Note, “The Constitutionality of Nonresident Tuition,” 55 Minn. L. Rev. 1139 (1971); Note, 8 Wake For. L. Rev. 265 (1972).
Petitioners were nonresidents, 21 years of age or more, when they first enrolled in the Law School of the University of North Carolina. It was stipulated that each petitioner had the intention of remaining in North Carolina indefinitely when he came into this state; that, “during the period of time in question,” each petitioner “established residence in the State of North Carolina for the purposes of voting and payment of taxes”; and that “the only reason why both were denied, after six months had elapsed, reclassification for tuition purpose [s] to that of resident is that neither maintained a residence in the State for six continuous months exclusive of time spent while in attendance at the University of North Carolina School of Law.”
[1] Petitioners concede that respondent could by regulation provide that a nonresident who enrolls in an institution of higher education in this state and continues his studies in such institution is presumed to be in this state primarily for educational purposes. Clarke v. Redeker, 259 F. Supp. at 122; 55 Minn. L. Rev. at 1158-59. Such a presumption is part of our law, aside from the regulations involved in this case. Hall v. Board of Elections, supra at 608, 187 S.E. 2d at 57. Petitioners contend that the absolute requirement that they reside in this state for at least six months preceding the date of their re-enrollment exclusive of any time spent in attendance in any institution of higher education, notwithstanding they have become domiciliaries, unconstitutionally denied to them rights accorded other domiciliaries of North Carolina.
Petitioners stress Carrington v. Rash, 380 U.S. 89, 13 L.Ed. 2d 675, 85 S.Ct. 775 (1965). In that case the United States Supreme Court invalidated a provision of the Texas Constitution prohibiting any member of the Armed Forces who moved his home to Texas during the course of his military duty from ever voting in any election in that state so long as *637he was a member of the Armed Forces. It was held that this provision established an “incontrovertible presumption of non-residence,” and, as applied to a bona fide domiciliary of Texas, violated the Equal Protection Clause of the Fourteenth Amendment. The real holding in Carrington was that a burden may not be imposed on, or a right denied to, a group labeled “nonresident,” when such labeling, with such attendant imposition or denial, is not reasonably related to the state interest it seeks to protect. In the present case, petitioners are not labeled as “nonresidents.” Whether the denial of a benefit to a certain class of residents (domiciliaries) in the present case, with its peculiar facts, is reasonably related to the state interest the classification is meant to protect, is not determined by the holding in Carrington, involving an entirely different set of facts.
In Shapiro v. Thompson, 394 U.S. 618, 22 L.Ed. 2d 600, 89 S.Ct. 1322 (1969), the Supreme Court held that state dura-tional residence requirements penalized the exercise of a person’s basic constitutional right to travel freely from one state to another by rendering him ineligible for welfare assistance, thereby depriving him of a right secured by the Equal Protection Clause of the Fourteenth Amendment. In Dunn v. Blumstein, 405 U.S. 330, 31 L.Ed. 2d 274, 92 S.Ct. 995 (1972), the Supreme Court considered Tennessee constitutional and statutory provisions which required residence in the state for one year for eligibility to vote in a state election. It was held that these provisions, as applied to a bona fide resident of Tennessee for less than one year, deprived such a resident of the rights to vote and to freedom of interstate travel in violation of the Equal Protection Clause of the Fourteenth Amendment.
In Shapiro and in Dunn, the state durational residence requirements were subjected to the most stringent test, namely, whether they were necessary to promote a compelling state interest.
[2] A person’s right to eligibility for in-state tuition is quite different from his basic constitutional right to travel freely from one state to another (Shapiro and Dunn) or his basic constitutional right to vote (Dunn). We take notice of the stipulation that the regulations in the present case “do not impede interstate travel.” Since they do not relate to basic constitutional rights, the regulations are to be tested by the less stringent traditional equal-protection standards.
*638 [3] The traditional equal-protection test does not require the very best classification in the light of a legislative or regulatory purpose; it does require that such classification in relation to such purpose attain a minimum (undefined and undefinable) level of rationality. “In the area of economics and social welfare, a state does not violate the Equal Protection Clause merely because the classifications made by its laws are imperfect. If the classification has some ‘reasonable basis,’ it does not offend the Constitution simply because the classification ‘is not made with mathematical nicety or because in practice it results in some inequality.’ ” Dandridge v. Williams, 397 U.S. 471, 485, 25 L.Ed. 2d 491, 501-02, 90 S.Ct. 1153, 1161 (1970).
In Landwehr v. Regents of University of Colorado, supra, and in Thompson v. Board of Regents of University of Neb., supra, statutory provisions' requiring as prerequisites for eligibility for in-state tuition, domiciliary status and actual residence within the state for a specified period exclusive of time spent in any institution of higher education, were upheld as reasonably related to a legitimate state objective. In Newman v. Graham, 82 Idaho 90, 349 P. 2d 716, 83 A.L.R. 2d 492 (1960), a similar requirement was held to be unconstitutional on the ground that it was “arbitrary, capricious and unreasonable.”
In the establishment and operation of its institutions of higher education, North Carolina’s obligation and primary purpose is to provide opportunities to citizens of this state. In furtherance thereof, in-state students are not required to pay tuition fees equivalent to the per capita cost but may enroll upon payment of the low in-state tuition. North Carolina is not in a position to provide opportunities to citizens of other states on this low-cost basis. Indeed, in view of present crowded conditions, only a limited number of persons domiciled in other states may be enrolled in our institutions of higher education.
[4] North Carolina’s right to require a domiciliary of another state to pay the higher out-of-state tuition fees upon his initial enrollment in an institution of higher education is not in dispute. The question is whether it is reasonable for the State to require that such person, in addition to being domiciled in North Carolina, be so domiciled while not in attendance at an institution of higher education for a six-month period, before he may qualify for in-state tuition.
*639We hold that such requirement is reasonable. The object is to assure that students who benefit from the in-state tuition subsidy the State provides for its citizens are in fact its own citizens. The Board of Trustees has determined that domicile alone is insufficent for this purpose. Domicile is solely a matter of physical presence plus the intent to make a home. All students enrolled in our institutions of higher education visibly meet the first requirement of domicile. The second requirement, however, is a concept in the mind of a particular student. It is true, as this Court emphasized in Hall v. Board of Elections, supra, that there are objective indicia by which a person’s statement of intent may be tested. Even so, a statement of intent is usually difficult to disprove; and the determination of a student’s domicile is especially difficult and subject to doubt. Ordinarily, whatever plans students may have with reference to where they will locate when they complete their attendance in an institution of higher education are in flux, frequently changed as unforeseeable circumstances and opportunities influence their future careers. Hence, the Board of Trustees has determined that domicile is only one of the prerequisites for in-state tuition status.
The State has no obligation to provide educational opportunities to noncitizens. Its interests require that it subsidize only those students whom it may be certain are North Carolina citizens. Moreover, uncertainty as to the circumstances under which the tuition status of students may change is fiscally and administratively undesirable.
The six-month nonattendance requirement adds objectivity and certainty to the requirement of domicile. It is a certainty not obtained by placing an unreasonable burden on students. Petitioners were not barred by respondent’s regulations from becoming domiciliaries of North Carolina. Nor were they barred from becoming eligible for in-state tuition. Rather, they were only required, if they wanted that status, to be domiciled in North Carolina for six months while not in the Law School. They must be deemed to have enrolled in the Law School with full knowledge of the tuition-status requirements. If they had complied with the requirements for eligibility for in-state tuition, their statement of intent to make North Carolina their home would have been borne out by an objective indication of their earnestness. That the Board of Trustees might have *640chosen other objective indicators to test the domiciliary intent of applicants for in-state tuition is not to say the one chosen was unreasonable. That there may be hardship cases resulting from the enforcement of these regulations is also not to say they are unreasonable. The constitutional test is whether the regulations have tended in general to assure that only North Carolina citizens get the benefit of in-state tuition. We hold that they have.
II
[6] Apart from the foregoing, petitioner Lamb contends he became eligible for in-state tuition status as of January, 1970, under Regulation No. 4, because of his marriage to a North Carolina domiciliary. Regulation No. 4 provides: “4. Married Students: The legal residence of a wife follows that of her husband, except that a woman currently enrolled as an instate student in an institution of higher education may continue as a resident even though she marries a nonresident. If the husband is a nonresident and separation or divorce occurs, the woman may qualify for in-state tuition after establishing her domicile in North Carolina for at least six months under the same conditions as she could if she were single.” Lamb contends that Regulation No. 4 grants in-state tuition to a nonresident woman who marries a North Carolina domiciliary solely on account of her sex and thus denies to men similarly situated a benefit in violation of the Equal Protection Clauses of the North Carolina and United States Constitutions.
Paragraph VIII of the Agreed Statement of Facts provides “ [t] hat the Board of Trustees Regulation No. 4 . . . permits a nonresident female to acquire a residence through marriage but does not give a nonresident male the same opportunity.” Although not included in the stipulations, the court found that Lamb “became a married man after his initial enrollment”; that “[h]is wife was a legal resident of the State of North Carolina”; and that “ [s] he was entitled to a lower tuition rate than her husband.” The date of Lamb’s marriage is undisclosed. Presumably, since the court found that “[s]he was entitled to a lower tuition rate than her husband,” Mrs. Lamb had been a domiciliary for at least six months exclusive of any time spent in attendance at any institution of higher education. The record indicates she had not enrolled in any institution of higher education but was employed at the Research Triangle Institute.
*641The foregoing constitutes1 the only pertinent factual data before us with reference to Lamb’s claim to in-state tuition status on account of his marriage.
Regulation No. 4 makes no provision for a change in the “legal residence” (domicile) of a nonresident man upon his marriage with a resident woman. The difference in the treatment of the sexes is this: When the nonresident woman marries the resident man, ipso facto she becomes a domiciliary of this state from the date of her marriage. Kirk v. Board of Regents of Univ. of California, supra. When the nonresident man marries the resident woman, he does not automatically become a domiciliary of this state but must establish that he has become a domiciliary by traditional proofs. For the reasons stated below, we need not consider whether this difference constitutes unreasonable discrimination.
[5] Independent of his marriage to a North Carolina resident, the stipulations establish that Lamb became a domiciliary of North Carolina as of a date prior to completion of his attendance in the Law School. Since Lamb’s domiciliary status has never been in question in this case, Lamb does not have standing to object to the automatic bestowal of domicile on a nonresident woman who marries a North Carolina domiciliary.
[6] As stated above, the regulations required that Lamb, to be eligible for in-state tuition status, show not only (1) that he was a domiciliary of North Carolina, but also (2) that he was a domiciliary of North Carolina for six continuous months exclusive of time spent while in attendance at the Law School. Under the regulations, domiciliary status was not equivalent to in-state tuition status. Although a woman was deemed a domiciliary of North Carolina from the date of her marriage, to become eligible for in-state tuition a married woman, just as Lamb or any other student, had to establish actual residence in this state for six continuous months exclusive of the time spent while in attendance at an institution of higher education. The regulations, including Regulation No. 4, placed upon all students domiciled in North Carolina, regardless of sex, the burden of showing that they had been domiciled in North Carolina for six months while not in attendance at an institution of higher education, to qualify for in-state tuition. Therefore, Lamb’s equal-protection argument fails.
*642Only two cases have come to our attention which involve regulations similar in some respects to Regulation No. 4.
In Kirk v. Board of Regents of Univ. of California, supra, the regulation provided that “ [t] he residence of the husband is the residence of the wife . ” The petitioner (wife), a resident of Ohio, married a California resident on July 1, 1967, and became a resident of California as of that date. The denial of her right to enroll in the University of California in September, 1967, as an in-state student was upheld because she was not “a resident student,” a term defined in the regulations as “any person who has been a bona fide resident of the State for more than one year immediately preceding the opening day of a semester during which he proposes to attend the university.” The court rejected the petitioner’s contention that the period of her husband’s residence in California preceding the marriage should be retroactively “tacked” to the period of her residence after the marriage.
In Clarke v. Redeker, 259 F. Supp. 117, a three-judge federal court upheld a regulation which provided: “The residence of a wife is that of her husband. A nonresident female student may attain residence through marriage, and correspondingly, a resident female student may lose residence by marrying a nonresident.”
We hold that the regulations as interpreted herein are valid and are not subject to successful attack by petitioners. Accordingly, the judgment of the court below is reversed.
Reversed.