#include <stdio.h>
 
// Iterative solution to calculate pow(x, n) using
// binary operators
int power(int x, unsigned n)
{
    // initialize result by 1
    int pow = 1;
 
    // do till n is not zero
    while (n)
    {
        // if n is odd, multiply result by x
        if (n & 1)
            pow *= x;
 
        // divide n by 2
        n = n >> 1;
 
        // multiply x by itself
        x = x * x;
    }
 
    // return result
    return pow;
}
 
// main function
int main(void)
{
    int x = -2;
    unsigned n = 10;
 
    printf("pow(%d,%d) = %d", x, n, power(x, n));
 
    return 0;
}

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