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INT34-EX2: Any positive integer value can be right shifted by the width of the promoted left hand operand. For example, positive >> 31 is valid for implementations where int has a width of 32 bits, even if positive is a smaller type, such as char. However, any portable shift expression that takes advantage of the full width of a signed integer is guaranteed to have a result of zero, so it is not useful to shift beyond the precision.
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