Merge pull request kothariji#522 from Yatindra29/master

added the fast power function, which calculates x^n in O(log n) time

Author: kothariji

Dynamic Programming/fast_power_function.cpp

@@ -0,0 +1,19 @@
+#include<iostream>
+using namespace std;
+int fast_power(int num,int power){
+    if(power==0){
+        return 1;
+    }
+    int p=fast_power(num,power/2);
+    p*=p;
+    if(power&1){
+        return num*p;
+    }
+    return p;
+}
+int main(){
+    int num,power;
+    cin>>num>>power;
+    int p=fast_power(num,power);
+    cout<<p<<endl;
+}