std::char_traits<CharT>::compare

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< cpp‎ | string‎ | char traits
static int compare( const char_type* s1, const char_type* s2, std::size_t count );
(until C++17)
static constexpr int compare( const char_type* s1, const char_type* s2, std::size_t count );
(since C++17)

Compares the first count characters of the character strings s1 and s2. The comparison is done lexicographically.

If count is zero, strings are considered equal.

Parameters

s1, s2 - pointers to character strings to compare
count - the number of characters to compare from each character string

Return value

Negative value if s1 is less than s2.

0 if s1 is equal to s2.

Positive value if s1 is greater than s2.

Exceptions

Throws nothing.

Complexity

Linear in count.