题解 | #自守数#

#include <stdio.h>
#include <math.h>

int main() {
    int n = 0;
    scanf("%d",&n);
    int count = 0;
    int num = 0;
    int numnum = 0;
    int findFlag = 0;
    for(int i = 0; i <= n; i++)
    {
        numnum = i*i;
        num = i;
        findFlag = 1;
        while(num > 0)
        {
            if(num%10 != numnum%10){
                findFlag = 0;
                break;}
            num = num/10;
            numnum = numnum/10;
        }
        if(findFlag) 
            count += findFlag;
    }
    printf("%d",count);

    return 0;
}