Range function for 2d loop in C++.

range2.cpp

#include <iostream>
#include <vector>
#include <utility>

template<typename T>
std::vector<std::pair<T, T>> range2(T start1, T end1, T start2, T end2) {
     std::vector<std::pair<T, T>> loopValues{};
	
     for (T i = start1; i < end1; ++i) {
          for (T j = start2; j < end2; ++j) {
	       loopValues.push_back(std::make_pair (i, j));
	  }
     }
	
     return loopValues;
}

int main() {
	
   for (auto p : range2(1, 3, 1, 3)) {
       std::cout << p.first << p.second << std::endl;
   }

   return 0;
}