input

The C++ input function allows you to declare variables and initialize them values loaded from cin or a file stream.

#include "input"
#include <iostream>
#include <fstream>

int main() {
  std::cin.exceptions(std::ios_base::badbit | std::ios_base::failbit);

  auto n=input<int>(); // input one integer
  auto [x,y]=input<double,double>(); // pair<double,double>
  auto v=input<double>(n); // vector<double>(n)
  auto t=input<int,char,double>(); // tuple<int,char,double>

  auto s=input(); // input to the end of line == getline(cin,s)
  
  std::ifstream fs("input.txt");
  // file contains
  // 5
  // 10 20 30 40 50
  auto m=input<int>(fs); // m=5
  auto a=input<int>(fs,m); // a={10,20,30,40,50}
  auto lines=input(fs,100); // input 100 lines or lines to EOF. Use -1 for input all lines
}