/C++/C++ sorting and keeping track of indexes

C++ sorting and keeping track of indexes

#include <iostream>
#include <vector>
#include <numeric>      // std::iota
#include <algorithm>    // std::sort, std::stable_sort

using namespace std;

template <typename T>
vector<size_t> sort_indexes(const vector<T> &v) {

  // initialize original index locations
  vector<size_t> idx(v.size());
  iota(idx.begin(), idx.end(), 0);

  // sort indexes based on comparing values in v
  // using std::stable_sort instead of std::sort
  // to avoid unnecessary index re-orderings
  // when v contains elements of equal values 
  stable_sort(idx.begin(), idx.end(),
       [&v](size_t i1, size_t i2) {return v[i1] < v[i2];});

  return idx;
}

Source: stackoverflow.com

Similar codes

4 votes247 views2 answers
Input pdf latex
C++
4 votes208 views1 answer
How to make i/o fast in c++
C++
0 vote255 views1 answer
How to use jwt in login api in node js
C++
0 vote244 views1 answer
Find with hash set
C++
0 vote235 views1 answer
Priority queue smallest first
C++
0 vote212 views10 answers
Python to c++ transpiler
C++
1 vote198 views1 answer
How to run a c++ program in the background
C++
0 vote432 views1 answer
Opengl draw house using glut c++
C++
8 votes215 views3 answers
C++ min
C++
0 vote229 views1 answer
How to input a vector when size is unknown
C++