Question

How to sort a vector of pairs based on the second element of the pair in descending order with C++

Answer 1

#include <algorithm>
#include <iostream>
#include <vector>
 
void print(const std::vector<std::pair<int, int>> vec) {
    for (const auto& val : vec) {
        std::cout << val.first << ", " << val.second << std::endl;
    }
}
 
int main()
{
    std::vector<std::pair<int, int>> vec = { {3, 8}, {5, 2}, {-4, 7} };
     
    std::sort(vec.begin(), vec.end(), [](auto &left, auto &right) {
        return left.second > right.second;
    });
 
    print(vec);
}
 
   
   
/*
run:
   
3, 8
-4, 7
5, 2
   
*/

 

70+ SQL courses for beginners and professionals