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Java-based LeetCode algorithm problem solutions, regularly updated

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package g0301_0400.s0371_sum_of_two_integers;

// #Medium #Top_Interview_Questions #Math #Bit_Manipulation #Udemy_Bit_Manipulation
// #2022_07_12_Time_0_ms_(100.00%)_Space_40.3_MB_(77.27%)

/**
 * 371 - Sum of Two Integers\.
 *
 * Medium
 *
 * Given two integers `a` and `b`, return _the sum of the two integers without using the operators_ `+` _and_ `-`.
 *
 * **Example 1:**
 *
 * **Input:** a = 1, b = 2
 *
 * **Output:** 3
 *
 * **Example 2:**
 *
 * **Input:** a = 2, b = 3
 *
 * **Output:** 5
 *
 * **Constraints:**
 *
 * *   `-1000 <= a, b <= 1000`
**/
public class Solution {
    public int getSum(int a, int b) {
        int ans = 0;
        int memo = 0;
        int exp = 0;
        int count = 0;
        while (count < 32) {
            int val1 = a & 1;
            int val2 = b & 1;
            int val = sum(val1, val2, memo);
            memo = val >> 1;
            val = val & 1;
            a = a >> 1;
            b = b >> 1;
            ans = ans | (val << exp);
            exp = plusOne(exp);
            count = plusOne(count);
        }
        return ans;
    }

    private int sum(int val1, int val2, int val3) {
        int count = 0;
        if (val1 == 1) {
            count = plusOne(count);
        }
        if (val2 == 1) {
            count = plusOne(count);
        }
        if (val3 == 1) {
            count = plusOne(count);
        }
        return count;
    }

    private int plusOne(int val) {
        return (-(~val));
    }
}