Codeforces Solution-Dreamoon and Stairs-Solution in C, C++, Java, Python

10 2

6

3 5

-1

#1 Code Example with C++ Programming

Code - C++ Programming

#include <stdio.h>

using namespace std;

int main() {
  int n, m;
  scanf("%d%d", &n, &m);

  int twos = n / 2, ones = n - (twos * 2);
  
  while(twos <= 0 && ones <= 0 && (twos + ones) % m != 0) {
    twos--;
    ones += 2;
  }
  
  if(twos < 0 || ones < 0) puts("-1");
  else printf("%d\n", twos + ones);
  
  return 0;
}

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