Coffee Cup Combo

Question

https://open.kattis.com/problems/coffeecupcomboopen.kattis.com

Solution

Idea

This is an easy question. The idea is to use two variables to store the coffee left after each lecture and the number of lectures Jonna can stay awake.

1. If you encounter a coffee machine, update the left to be 2 and increment sum by 1.

2. Otherwise, if there is coffee left, decrement left by 1 and increment sum by 1.

Code

https://github.com/mendax1234/Coding-Problems/blob/main/kattis/coffeecupcombo/coffeecupcombo.c

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

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

  char *line = calloc(n+2, sizeof(char));
  
  if (fgets(line, n+2, stdin))
  {
    line[strcspn(line, "\n")] = 0;
  }
 
  int sum = 0;
  int left = 0;
  for (int i = 0; i < n; i += 1)
  {
    if (line[i] == '1')
    {
      left = 2;
      sum += 1;
    }
    else if (left != 0)
    {
      left -= 1;
      sum += 1;
    }
  }
  printf("%d\n", sum);
}