371

Author: yubinbai

README.md

@@ -3,6 +3,7 @@ Leetcode solutions in C++, Java, Python
 
 |#|Title|Solution|Difficulty|
 |---|-----|--------|----------|
+|371|[Sum of Two Integers](./src/sum_of_two_integers)|[C++](./src/sum_of_two_integers)|Easy|
 |370|[Range Addition](./src/range_addition)|[C++](./src/range_addition)|Medium|
 |369|[Plus One Linked List](./src/plus_one_linked_list)|[C++](./src/plus_one_linked_list)|Medium|
 |368|[Largest divisible subset](./src/largest_divisible_subset)|[C++](./src/largest_divisible_subset)|Medium|

src/sum_of_two_integers/Makefile

@@ -0,0 +1,6 @@
+all:
+	clang++ main.cpp -o main.o -std=c++11
+
+run:
+	clang++ main.cpp -o main.o -std=c++11
+	./main.o

src/sum_of_two_integers/README.md

@@ -0,0 +1,7 @@
+Problem
+===
+late the sum of two integers a and b, but you are not allowed to use the operator + and -.
+
+Example:
+Given a = 1 and b = 2, return 3.
+

src/sum_of_two_integers/main.cpp

@@ -0,0 +1,40 @@
+#include <algorithm>
+#include <cstdlib>
+#include <iostream>
+#include <map>
+#include <queue>
+#include <set>
+#include <sstream>
+#include <stack>
+#include <string>
+#include <unordered_map>
+#include <unordered_set>
+#include <vector>
+
+using namespace std;
+
+class Solution {
+public:
+  int getSum(int a, int b) {
+    int x = a, y = b;
+    while (y != 0) {
+      int xx = x ^ y;
+      int yy = x & y;
+      x = xx;
+      y = yy << 1;
+    }
+    return x;
+  }
+};
+
+int main() {
+  Solution sol;
+
+  cout << sol.getSum(1, 2) << endl;
+
+  cout << sol.getSum(2, 2) << endl;
+
+  cout << sol.getSum(3, 5) << endl;
+
+  return 0;
+}