class Solution { public double myPow(double x, int n) { if(n==0) return 1; if(n==1 || x==1 || x==0) return x; if(n<0) return (1/x) * myPow(1/x,-(n+1)); return n%2==0 ? myPow(x*x, n/2) : x * myPow(x*x, n/2); } }