Question

In C (linux) how will I be able to find out if the squareroot of a number is and integer or a floating point.
I want to write a program using a function pointer which adds up all the Perfect squares
upto the limit sepcified.

Answer 1

Here you go. Compile it with -lm on Linux.

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

int checkRoot(double n) {
    long n_sqrt = (long)(sqrt(n)+0.5);
    return n_sqrt*n_sqrt == n;
}

int main() {
    double n = 9.0;
    if(checkRoot(n)) {
        puts("Perfect root.");
    }
    else {
        puts("Not quite.");
    }
    return EXIT_SUCCESS;
}

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