K&R Exercise 1.8 Write a program to count blanks, tabs and newlines

Problem Statement:

Exercise 1-8: Write a program to count blanks, tabs and newlines.

Solution:

Blank is ' ', tab is '\t' and newline is '\n'.

Strategy

• Lets take one character time as the input using getchar() in a loop.
• Each character is compared against ' ', '\t', '\n'.
• If it matches then appropriate counters are incremented.
• Loop will end when the character input is EOF.

Implementation is as below

#include <stdio.h>
int main()
{
   int c;
   int count_blank = 0;
   int count_tab = 0;
   int count_newline = 0;

   while((c = getchar()) != EOF) {
      if(c == ' ') {
         count_blank++;
      }else if(c == '\t'){
         count_tab++;
      }else if(c == '\n'){
         count_newline++;
      }
   }
   printf("Total Blank is %d\n", count_blank);
   printf("Total Tab is %d\n", count_tab);
   printf("Total New line is %d\n", count_newline);

   return 0;
}

Output
Input from keyboard

$./e_1_08.out
This is very long line.
This is yet  another  line.      
Total Blank is 8
Total Tab is 2
Total New line is 2

Using Pipe

$ cat text 
This is very long   line.
This is yet  another  line.
$ cat text | ./e_1_08.out
Total Blank is 9
Total Tab is 3
Total New line is 2

Using file redirection

$ ./e_1_08.out < text
Total Blank is 9
Total Tab is 3
Total New line is 2

Links

Next Article - K&R Exercise 1.9 Replace multiple blank with single blank
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