#include <stdio.h>
// https://stackoverflow.com/a/1343685/5305370
int isqrt(int n)
{
int b = 0;
while(n >= 0)
{
n = n - b;
b = b + 1;
n = n - b;
}
return b - 1;
}
int main(void) {
int a = 9;
int b = isqrt(a);
printf("a = %d, sqrt(a) = b = %d\n", a
, b
); return 0;
}
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