@YipCubed/

# leet-sum-of-two-integers

## No description

Files
• main.cpp
main.cpp
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```
```#include <cstring>
#include <climits>
#include <iostream>
#include <map>
#include <queue>
#include <set>
#include <stack>
#include <vector>

using namespace std;

// Live coding problems, watch at
// https://www.twitch.tv/yipcubed
//

// makes code faster, but larger. Just for LeetCode fun!
#pragma GCC optimise ("Ofast")

// makes stdin not synced so it is faster. Just for LeetCode fun!
static auto x = [](){ios_base::sync_with_stdio(false); cin.tie(NULL); return NULL;}();

class Solution {
public:
// 0010 = 2
// 1010 = 10
// x = 1010, y = 0010
// carry = x & y = 0010
// x = x ^ y = 1000
// y = carry << 1 = 0100
// carry = x & y = 1100
// x = x ^ y = 0000
int getSum(int a, int b) {
unsigned int x = a;
unsigned int y = b;
while (y != 0)  {

// if bit-i is set in x and y then carry != 0
unsigned int carry = x & y;

// if bit-i is 0 and 1, get 1
// if bit-i is 0 and 0, get 0
// if bit-i is 1 and 1, get 0 -- this bit generated the carry
x = x ^ y;

// move carry left from bit-i
// if carry was generated from i=2, now bit at i=4 is set
y = carry << 1;
}
return x;
}
};

void test1() {
Solution S;
cout << "3? " << S.getSum(1, 2) << endl;
cout << "12? " << S.getSum(10, 2) << endl;
cout << "-8? " << S.getSum(-10, 2) << endl;
cout << "8? " << S.getSum(10, -2) << endl;
}

void test2() {
Solution S;
}

void test3() {
Solution S;
}

int main() {
test1();
test2();
test3();
cout << "Done!" << endl;

return 0;
}

```