(30 + 25) ^ 2 = 3025

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

// 3025 = (30 + 25) ^ 2

void halfsqaure(int n, int len)
{
    if(len % 2 == 0) // Len is even
    {
        int left, right;
        int divider_mod = pow(10, len / 2); // Modulo divider to find the right side

        left = n * pow(10, (-1) * ((len / 2))); // Left side: n * 10^-(len/2)
        right = n % divider_mod;

        int sum = left + right;
        int sum_pow = pow(sum, 2);

        if(sum_pow == n)
        {
            printf("Yes!");
            return;
        }
    }

    // length is not even or the result is false
    printf("No!");
}

void main()
{
    halfsqaure(3025, 4);
}