C++ Standard Library Algorithms std::min_element


Example

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

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

Effects

Finds the minimum element in a range

Parameters

first - iterator pointing to the beginning of the range
last - iterator pointing to the end of the range comp - a function pointer or function object that takes two arguments and returns true or false indicating whether argument is less than argument 2. This function should not modify inputs

Return

Iterator to the minimum element in the range

Complexity

Linear in one less than the number of elements compared.

Example

#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;
}

Output

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