#include <stdio.h>
 
// Naive recursive solution to calculate pow(x, n)
// using Divide & Conquer
int power(int x, unsigned n)
{
    // base condition
    if (n == 0)
        return 1;
 
    if (n & 1) // if n is odd
        return x * power(x, n / 2) * power(x, n / 2);
 
    // else n is even
    return power(x, n / 2) * power(x, n / 2);
}
 
// 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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