Average Character

Question

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

Solution

Idea

The basic idea is easy, just to get the average ASCII value of each character in the input string.

However, if C is the language being used, things get a bit tricky regarding the input. Here, we can only use fgets() to read the input because white space characters cannot be ignored in this question. So, the correct way to read the input is below:

#define MAX_LEN 102

if (fgets(string, MAX_LEN, stdin))
{
  string[strcspn(string, "\n")] = 0;
}

Here the MAX_LEN is 2 characters more than 100 (the actual length of the string). This is because:

1. Add 1 to take the null character into account (the property of string in C)

2. Add 1 to take the \n character which is read by fgets() (the property of fgets() in C)

Code

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

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

#define MAX_LEN 102

char get_average_ascii(char string[MAX_LEN])
{
  long i = 0;
  long sum = 0;
  while(string[i] != 0)
  {
    sum += (long)string[i];
    i += 1;
  }
  long avg = sum / i;
  return (char)avg;
}

int main()
{
  char string[MAX_LEN];

  if (fgets(string, MAX_LEN, stdin))
  {
    string[strcspn(string, "\n")] = 0;
  }

  putchar(get_average_ascii(string));
}