🚀 17-Jul-2020

Author: sureshmangs

Diff for: competitive programming/leetcode/2020-July-Challenge/Day-16-Pow(x, n).cpp

@@ -0,0 +1,48 @@
+Implement pow(x, n), which calculates x raised to the power n (xn).
+
+Example 1:
+
+Input: 2.00000, 10
+Output: 1024.00000
+Example 2:
+
+Input: 2.10000, 3
+Output: 9.26100
+Example 3:
+
+Input: 2.00000, -2
+Output: 0.25000
+Explanation: 2-2 = 1/22 = 1/4 = 0.25
+Note:
+
+-100.0 < x < 100.0
+n is a 32-bit signed integer, within the range [−231, 231 − 1]
+
+
+
+
+
+
+
+
+
+
+
+class Solution {
+public:
+    double myPow(double x, int n) {
+        double res=1;
+        bool neg=false;
+        if(n<0) neg=true;
+        n=abs(n);
+        while(n){
+            if(n%2!=0){
+                if(neg) res=res/x;
+                 else res=res*x;
+            }
+            x*=x;
+            n/=2;
+        }
+        return res;
+    }
+};

Diff for: competitive programming/leetcode/50. Pow(x, n).cpp

@@ -0,0 +1,48 @@
+Implement pow(x, n), which calculates x raised to the power n (xn).
+
+Example 1:
+
+Input: 2.00000, 10
+Output: 1024.00000
+Example 2:
+
+Input: 2.10000, 3
+Output: 9.26100
+Example 3:
+
+Input: 2.00000, -2
+Output: 0.25000
+Explanation: 2-2 = 1/22 = 1/4 = 0.25
+Note:
+
+-100.0 < x < 100.0
+n is a 32-bit signed integer, within the range [−231, 231 − 1]
+
+
+
+
+
+
+
+
+
+
+
+class Solution {
+public:
+    double myPow(double x, int n) {
+        double res=1;
+        bool neg=false;
+        if(n<0) neg=true;
+        n=abs(n);
+        while(n){
+            if(n%2!=0){
+                if(neg) res=res/x;
+                 else res=res*x;
+            }
+            x*=x;
+            n/=2;
+        }
+        return res;
+    }
+};

Diff for: mathematical/x_power_n_negative_decimal.cpp

@@ -0,0 +1,27 @@
+#include<bits/stdc++.h>
+using namespace std;
+
+double power(double x, int n) {
+    double res=1;
+    bool neg=false;
+    if(n<0) neg=true;
+    n=abs(n);
+    while(n){
+        if(n%2!=0){
+            if(neg) res=res/x;
+                else res=res*x;
+        }
+        x*=x;
+        n/=2;
+    }
+    return res;
+}
+
+int main(){
+    int x, n;
+    cin>>x>>n;
+    // x^n
+    cout<<double(power(x, n));
+
+    return 0;
+}