常用stl

rotate & rotate_copy

循环旋转序列内元素

template< class ForwardIt >
ForwardIt rotate(ForwardIt first, ForwardIt middle, ForwardIt last);


template< class ForwardIt1, class ForwardIt2 >
ForwardIt2 rotate_copy(ForwardIt1 first, ForwardIt1 middle, ForwardIt1 last, ForwardIt2 d_first);

accumulate

区间计算,具体计算函数为第四个参数(默认为加法), init为初始值

#include <numeric>

T accumulate(InputIt first, InputIt last, T init, BinaryOperation op);

ex:

#include <numeric>
#include <vector>
#include <string>
#include <iostream>
using namespace std;

int main() {
    vector<string> words = {"Hello", " ", "World", "!"};
    string sentence = accumulate(words.begin(), words.end(), string(""));
    cout << sentence << endl; // 输出 "Hello World!"
}

以及对浮点数需要double(0)或(0.0)