Detect if two integers have opposite signs | GeeksforGeeks

Given two signed integers, write a function that returns true if the signs of given integers are different, otherwise false. The function should not use any of the arithmetic operators.
The sign bit is 1 in negative numbers, and 0 in positive numbers. The XOR of x and y will have the sign bit as 1 iff they have opposite sign. In other words, XOR of x and y will be negative number number iff x and y have opposite signs

bool oppositeSigns(int x, int y)

{

    return ((x ^ y) < 0);

}

bool oppositeSigns(int x, int y)

{

    return ((x ^ y) >> 31);

}

bool oppositeSigns(int x, int y) {     return (x < 0)? (y >= 0): (y < 0); }

The first method is more efficient. The first method uses a bitwise XOR and a comparison operator. The second method uses two comparison operators and a bitwise XOR operation is more efficient compared to a comparison operation.

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