euler62.c


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#include <stdio.h>

struct cube
{
	long long minc;
	int nc;
};

struct cube cubes[10000000];
int ncubes;

int isperm(long long x, long long y)
{
	int a[10];
	for (int i = 0; i < 10; i++)
		a[i] = 0;

	while (x) {
		a[x%10]++;
		x /= 10;
	}
	while (y) {
		a[y%10]--;
		y /= 10;
	}
	for (int i = 0; i < 10; i++) {
		if (a[i] != 0)
			return 0;
	}
	return 1;
}

int main()
{
	ncubes = 0;
	int i = 0;
	while (1) {
		long long t = (long long)i*i*i;
		int hasperm = 0;
		for (int j = 0; j < ncubes; j++) {
			if (isperm(cubes[j].minc, t)) {
				cubes[j].nc++;
				if (cubes[j].nc == 5) {
					printf("%lld\n", cubes[j].minc);
					return 0;
				}
				hasperm = 1;
				break;
			}
		}
		if (hasperm == 0) {
			cubes[ncubes].minc = t;
			cubes[ncubes].nc = 1;
			ncubes++;
		}
		i++;
	}
}