/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 votes101 views1 answer
Eosio multi index secondary index
C++
0 vote144 views1 answer
Inbuilt function for bin to dec in c++
C++
0 vote108 views1 answer
Cstring to string
C++
3 votes55 views1 answer
(a) one-dimensional arrays and multidimensional arrays in c++
C++
0 vote99 views1 answer
Random 1 diem tren man hinh bang dev c
C++
8 votes103 views3 answers
C++ check substring
C++
39 votes144 views6 answers
C++ print hello world
C++
0 vote134 views1 answer
C++ average
C++
3 votes59 views2 answers
C++ input integer
C++
0 vote86 views1 answer
Flag controlled while loop c++
C++