package 递归;

public class 高效n次幂 {
    
    

    public static void main(String[] args) {
    
    

        int a =pom(2,10);

        System.out.println(a);

    }


    private static int pom(int a, int n) {
    
    

        if (n == 0)
            return 1;

        int res = a;
        int ex = 1;

        while (res << 1 < n) {
    
    
            res = res * res;
            ex <<= 1;
        }
        return res * pom(a, n - ex);

    }

}