Average word length

Hi, I'm fairly new. I just started a few weeks ago my C programming course in university (I'm a mechanical engineering student).
I wanted to create a program that calculates the average length of words in a sentence.
I tried this:

Code:

---

#include<stdio.h>

int length = 0, words = 1;

int main()
{
  printf("Enter sentence: ");
 
  while(getchar() != '\n')
  {
    length++;
    if(getchar() == ' ')
      words++;
    }
    printf("The average length of a word is: %d", length / words);

return 0;
}

---

I don't understand why but apparently the loop ends prematurely after the first space the program encounters.
For example I gave "Ciao Mondo" as an input and the values of length and words were respectively 5 and 1.
Any idea what might cause this?

You have several problems here.

When your first getchar() gets a space, the second gets the next char after the space, turning the whole line into one big word!

Look at the following with my changes and notes:

Code:

---

#include <stdio.h>

int main()
{
  // Make all your variables local, NOT global!
  int length = 0, words = 0; // No words have been entered
  int ch = 0; // To capture the value returned from getchar()

  printf("Enter sentence: ");

  while((ch = getchar()) != '\n')
  {
      length++;
//    if(getchar() == ' ') // This would get the next char in the buffer
      if(ch == ' ') // Check the value captured in the getchar() above
        words++;
  }
  printf("The average length of a word is: %d\n", length / words);

  return 0;
}

---

Oh I see! I thought the program would consider the same char for the whole duration of the loop!
Thank you so much! As soon as I can I’m going to modify my program!

I do see why you initialize words to 1; I would have written this a little differently.

I’d be curious to see how you would have written this! Could you show me?

Quote:

---

Originally Posted by PondaKonatsu

I’d be curious to see how you would have written this! Could you show me?

---

Following the style of your code, this might be my version:

Code:

---

#include <stdio.h>
#include <ctype.h>  // For isspace()

/**
 ** This version still has it's problems.
 **  Empty line, just the newline
 **  Multiple whitespace chars between the words
 **  Leading and trailing whitespace chars
 **/

int main(void)
{
  // Make all your variables local, NOT global!
  int length = 0, words = 0; // No words have nbeen entered
  int ch = 0; // To capture the value returned from getchar()

  printf("Enter sentence: ");

  while(1)  // Infinite loop until break;
  {
      ch = getchar();

      if(ch == '\n')
      {
        words++; // End of line, count last word
        break;
      }

      // Else check for end of word, checking for any whitespace char, other than a newline
      // Think tab, vertical tab, formfeed, etc...
      if(isspace(ch)) // Check the value captured in the getchar() above
      {
        words++;
      }
      else
      {
        length++; // Only count letters in the word, not any spaces
      }
  }
  printf("Total length of the letters in words: %d, Number of words: %d\n", length, words);

  // Choose one of the following:
  printf("The average length of a word is: %d\n", length / words); // Integer division
  printf("The average length of a word is: %f\n", (float) length / words); // Floating point division

  return 0;
}

---

A more advanced version that I would normally use, would be to input the entire line using fgets(), then parse the line using strtok(). You may not have studied these functions yet. There are other solutions as well, such as using scanf().

Unfortunately I haven't seen yet the functions you mentioned. I just studied the loops and the different types of formats for inputs. Still, I could understand the last code you sent me! Thank you very much for your guidance and patience! Have a nice day!

Another one for your study:

Code:

---

/* Compile with GCC:

  gcc -o test test.c

  Add -DDEBUG with you want to see 'debug' messages. */
#define _GNU_SOURCE
#include <stdlib.h>
#include <stdio.h>
#include <string.h>

#define SEPARATORS " \t,.;:?!<>[]{}#$%*()_+="

int main( int argc, char *argv[] )
{
  char *p;
  size_t words, size;

#ifdef DEBUG
  size_t n = 0;
#endif

  if ( argc != 2 )
  {
    fprintf( stderr, "Usage: %s <string>\n", basename( *argv ) );
    return EXIT_FAILURE;
  }

  words = size = 0;

  p = strtok( *++argv, SEPARATORS );

  while ( p )
  {
    size_t len;

    words++;

    if ( len = strlen( p ) )
      size += len;

#ifdef DEBUG
    printf( "%zu: \"%s\" (size=%zu, words=%zu)\n", ++n, p, size, words );
#endif

    p = strtok( NULL, SEPARATORS );
  }

  printf( "%zu words found.\n"
          "Average words length: %.3f characters.\n", words, ( double )size / words );

  return EXIT_SUCCESS;
}

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