The header <algorithm> defines a collection of functions especially designed to be used on ranges of elements.

A range is any sequence of objects that can be accessed through iterators or pointers, such as an array or an instance of some of the STL containers . Notice though, that algorithms operate through iterators directly on the values, not affecting in any way the structure of any possible container (it never affects the size or storage allocation of the container).

Functions in <algorithm>

Non-modifying sequence operations :
for_each Apply function to range (template function)
find Find value in range (function template)
find_if Find element in range (function template)
find_end Find last subsequence in range (function template)
find_first_of Find element from set in range (function template)
adjacent_find Find equal adjacent elements in range (function template)
count Count appearances of value in range (function template)
count_if Return number of elements in range satisfying condition (function template)
mismatch Return first position where two ranges differ (function template)
equal Test whether the elements in two ranges are equal (function template)
search Find subsequence in range (function template)
search_n Find succession of equal values in range (function template)


Modifying sequence operations :
copy Copy range of elements (function template)
copy_backward Copy range of elements backwards (function template)
swap Exchange values of two objects (function template)
swap_ranges Exchange values of two ranges (function template)
iter_swap Exchange values of objects pointed by two iterators (function template)
transform Apply function to range (function template)
replace Replace value in range (function template)
replace_if Replace values in range (function template)
replace_copy Copy range replacing value (function template)
replace_copy_if Copy range replacing value (function template)
fill Fill range with value (function template)
fill_n Fill sequence with value (function template)
generate Generate values for range with function (function template)
generate_n Generate values for sequence with function (function template)
remove Remove value from range (function template)
remove_if Remove elements from range (function template)
remove_copy Copy range removing value (function template)
remove_copy_if Copy range removing values (function template)
unique Remove consecutive duplicates in range (function template)
unique_copy Copy range removing duplicates (function template)
reverse Reverse range (function template)
reverse_copy Copy range reversed (function template)
rotate Rotate elements in range (function template)
rotate_copy Copy rotated range (function template)
random_shuffle Rearrange elements in range randomly (function template)
partition Partition range in two (function template)
stable_partition Partition range in two - stable ordering (function template)


Sorting :
sort Sort elements in range (function template)
stable_sort Sort elements preserving order of equivalents (function template)
partial_sort Partially Sort elements in range (function template)
partial_sort_copy Copy and partially sort range (function template)
nth_element Sort element in range (function template)


Binary search (operating on sorted ranges):
lower_bound Return iterator to lower bound (function template)
upper_bound Return iterator to upper bound (function template)
equal_range Get subrange of equal elements (function template)
binary_search Test if value exists in sorted array (function template)


Merge (operating on sorted ranges):
merge Merge sorted ranges (function template)
inplace_merge Merge consecutive sorted ranges (function template)
includes Test whether sorted range includes another sorted range (function template)
set_union Union of two sorted ranges (function template)
set_intersection Intersection of two sorted ranges (function template)
set_difference Difference of two sorted ranges (function template)
set_symmetric_difference Symmetric difference of two sorted ranges (function template)


Heap :
push_heap Push element into heap range (function template)
pop_heap Pop element from heap range (function template)
make_heap Make heap from range (function template)
sort_heap Sort elements of heap (function template)


Min/max :
min Return the lesser of two arguments (function template)
max Return the greater of two arguments (function template)
min_element Return smallest element in range (function template)
max_element Return largest element in range (function template)
lexicographical_compare Lexicographical less-than comparison (function template)
next_permutation Transform range to next permutation (function template)
prev_permutation Transform range to previous permutation (function template)

具体的函数就不翻译了，个人英文水平不高，呵呵。不懂的单词http://translate.google.cn 翻译一下。