/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

3 votes104 views1 answer
C++ generate random char
C++
2 votes104 views4 answers
Substring in c++
C++
0 vote129 views1 answer
For_each c++
C++
5 votes106 views1 answer
How to print list in c++
C++
1 vote100 views1 answer
C++ vector move element to front
C++
1 vote112 views1 answer
Select one random element of a vector in c++
C++
-1 vote108 views1 answer
C++ forloop
C++
0 vote119 views1 answer
Sort html elements in Jquery on condition
C++
0 vote97 views2 answers
Default order in set in c++
C++
0 vote125 views1 answer
Find first of a grammar
C++