stdmin 元素

template <class ForwardIterator>
ForwardIterator min_element (ForwardIterator first, ForwardIterator last);

template <class ForwardIterator, class Compare>
ForwardIterator min_element (ForwardIterator first, ForwardIterator last,Compare comp);

效果

查找范围中的最小元素

参数

first -迭代指向范围的开头
last -迭代指向范围 comp 的端部 -的函数指针或函数对象有两个参数和返回真或假,指示参数是否小于参数 2.本功能不应该修改输入

返回

迭代器到范围中的最小元素

复杂

线性比一个元素的数量少。

#include <iostream>
#include <algorithm>
#include <vector>
#include <utility>  //to use make_pair

using namespace std;

//function compare two pairs
bool pairLessThanFunction(const pair<string, int> &p1, const pair<string, int> &p2)
{
  return p1.second < p2.second;
}

int main(int argc, const char * argv[]) {
  
  vector<int> intVec {30,200,167,56,75,94,10,73,52,6,39,43};
  
  vector<pair<string, int>> pairVector = {make_pair("y", 25), make_pair("b", 2), make_pair("z", 26), make_pair("e", 5) };
  
  
  // default using < operator
  auto minInt = min_element(intVec.begin(), intVec.end());
  
  //Using pairLessThanFunction
  auto minPairFunction = min_element(pairVector.begin(), pairVector.end(), pairLessThanFunction);
  
  
  //print minimum of intVector
  cout << "min int from default: " << *minInt << endl;
  
  //print minimum of pairVector
  cout << "min pair from PairLessThanFunction: " << (*minPairFunction).second << endl;
  
  return 0;
}

输出

min int from default: 6
min pair from PairLessThanFunction: 2