std::stable_partition

 

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all_ofany_ofnone_of (C++11)(C++11)(C++11) for_each countcount_if mismatch equal	findfind_iffind_if_not (C++11) find_end find_first_of adjacent_find search search_n
Modifying sequence operations
copycopy_if (C++11) copy_n (C++11) copy_backward move (C++11) move_backward (C++11) fill fill_n transform generate generate_n removeremove_if remove_copyremove_copy_if	replacereplace_if replace_copyreplace_copy_if swap swap_ranges iter_swap reverse reverse_copy rotate rotate_copy random_shuffleshuffle  (C++11) unique unique_copy
Partitioning operations
is_partitioned (C++11) partition partition_copy (C++11)	stable_partition partition_point (C++11)
Sorting operations (on sorted ranges)
is_sorted (C++11) is_sorted_until (C++11) sort	partial_sort partial_sort_copy stable_sort nth_element
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lower_bound upper_bound	binary_search equal_range
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merge inplace_merge includes	set_difference set_intersection set_symmetric_difference set_union
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is_heap (C++11) is_heap_until (C++11) make_heap	push_heap pop_heap sort_heap
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max max_element min min_element minmax (C++11) minmax_element (C++11)	lexicographical_compare is_permutation (C++11) next_permutation prev_permutation
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iota (C++11) accumulate inner_product	adjacent_difference partial_sum
C library
qsort	bsearch

 

Defined in header <algorithm>
template< class BidirIt, class UnaryPredicate > BidirIt stable_partition( BidirIt first, BidirIt last, UnaryPredicate p );

Reorders the elements in the range [first, last) in such a way that all elements for which the predicate p returns true precede the elements for which predicate p returns false. Relative order of the elements is preserved.

Parameters

first, last	-	the range of elements to reorder
p	-	unary predicate which returns ​true if the element should be ordered before other elements. The signature of the predicate function should be equivalent to the following:  bool pred(const Type &a); The signature does not need to have const &, but the function must not modify the objects passed to it. The type Type must be such that an object of type BidirIt can be dereferenced and then implicitly converted to Type. ​
Type requirements
- BidirIt must meet the requirements of ValueSwappable and BidirectionalIterator.
- The type of dereferenced BidirIt must meet the requirements of MoveAssignable and MoveConstructible.
- UnaryPredicate must meet the requirements of Predicate.

Return value

Iterator to the first element of the second group

Complexity

Exactly last-first applications of the predicate and at most (last-first)*log(last-first) swaps if there is insufficient memory or linear number of swaps if sufficient memory is available.

Example

Run this code

#include <iostream>
#include <algorithm>
#include <vector>
 
int main()
{
    std::vector<int> v{0, 0, 3, 0, 2, 4, 5, 0, 7};
    std::stable_partition(v.begin(), v.end(), [](int n){return n>0;});
    for (int n : v) {
        std::cout << n << ' ';
    }
    std::cout << '\n';
}

Output:

3 2 4 5 7 0 0 0 0

See also

partition

divides a range of elements into two groups (function template)