C語言求200000以內的自守數

/*自守數是指一個數的平方的尾數等於該數自身的自然數*/
/*如25*25=625  76*76=5776 9376*9376=87909376*/
#include <stdio.h>

int main(void)
{
	for (unsigned int i = 1; i < 200000; i++)
	{
		unsigned long long square = (unsigned long long)i * i;
		unsigned int _i = i,cnt = 1;

		while (_i)
		{
			_i /= 10;
			cnt *= 10;
			if ((_i == 0) && ((square % cnt) == (i % cnt)))
				printf("%d	%lld\n",i, square);
		}
	}

	return 0;
}