# operator==,!=,<,<=,>,>=(std::map)

From cppreference.com
< cpp‎ | container‎ | map

template< class Key, class T, class Compare, class Alloc > bool operator==( const std::map <Key,T,Compare,Alloc>& lhs, const std::map <Key,T,Compare,Alloc>& rhs ); | (1) |
template< class Key, class T, class Compare, class Alloc > bool operator!=( const std::map <Key,T,Compare,Alloc>& lhs, const std::map <Key,T,Compare,Alloc>& rhs ); | (2) |
template< class Key, class T, class Compare, class Alloc > bool operator<( const std::map <Key,T,Compare,Alloc>& lhs, const std::map <Key,T,Compare,Alloc>& rhs ); | (3) |
template< class Key, class T, class Compare, class Alloc > bool operator<=( const std::map <Key,T,Compare,Alloc>& lhs, const std::map <Key,T,Compare,Alloc>& rhs ); | (4) |
template< class Key, class T, class Compare, class Alloc > bool operator>( const std::map <Key,T,Compare,Alloc>& lhs, const std::map <Key,T,Compare,Alloc>& rhs ); | (5) |
template< class Key, class T, class Compare, class Alloc > bool operator>=( const std::map <Key,T,Compare,Alloc>& lhs, const std::map <Key,T,Compare,Alloc>& rhs ); | (6) |

Compares the contents of two containers.

1-2) Checks if the contents of `lhs` and `rhs` are equal, that is, they have the same number of elements and each element in `lhs` compares equal with the element in `rhs` at the same position.
3-6) Compares the contents of `lhs` and `rhs` lexicographically. The comparison is performed by a function equivalent to std::lexicographical_compare. This comparison ignores the container's ordering Compare.

### Parameters

lhs, rhs | - | containers whose contents to compare
- `T, Key` must meet the requirements of EqualityComparable in order to use overloads (1-2).
- `Key` must meet the requirements of LessThanComparable in order to use overloads (3-6). The ordering relation must establish total order.

### Return value

1) true if the contents of the containers are equal, false otherwise
2) true if the contents of the containers are not equal, false otherwise
3) true if the contents of the `lhs` are lexicographically less than the contents of `rhs`, false otherwise
4) true if the contents of the `lhs` are lexicographically less than or equal the contents of `rhs`, false otherwise
5) true if the contents of the `lhs` are lexicographically greater than the contents of `rhs`, false otherwise
6) true if the contents of the `lhs` are lexicographically greater than or equal the contents of `rhs`, false otherwise

### Complexity

1-2) Constant if `lhs` and `rhs` are of different size, otherwise linear in the size of the container
3-6) Linear in the size of the container
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