How Do Unsigned Integers Handle Overflow in C/C ?

Unsigned Integer Overflow in C/C

When working with integer arithmetic, it's important to be aware of potential overflow conditions. In particular, unsigned integers behave differently than signed integers when overflowing.

According to an article you're reading, "a computation involving unsigned operands can never overflow." This is because the result is "reduced modulo to the number that is one greater than the largest value that can be represented by the resulting type."

In simpler terms, this means that when an unsigned integer computation exceeds its maximum value, it "wraps around" to 0. Here's an example:

unsigned int value = UINT_MAX; // Maximum unsigned integer value

value++; // Increment value by 1

// value now equals 0 because it has "wrapped around"

This behavior is analogous to the modulo operation, where:

value % (UINT_MAX + 1) == value

Therefore, when working with unsigned integers, it's crucial to be aware of this "wrap-around" behavior to avoid unexpected results or security vulnerabilities.

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