371. sum of two integers

Calculate the sum of two integers a and b, but you are not allowed to use the operator + and -.

Example 1:

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Input: a = 1, b = 2
Output: 3

Example 2:

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Input: a = -2, b = 3
Output: 1
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class  {
public int getSum(int a, int b) {
int result = a ^ b;
int carry = a & b;
carry <<= 1;
if (carry != 0) {
result = getSum(result, carry);
}
return result;
}
}