Learn to Program with C_ Learn to Program using the Popular C Programming Language ( PDFDrive )

Chapter 6 ■ Characters
number of characters in the line and the other to count the number of blanks. The logic could be
expressed as:
set number of characters and number of blanks to 0
while we are not at the end-of-line
read a character
add 1 to number of characters
if character is a blank then add 1 to number of blanks
endwhile
This logic is implemented as shown in Program P6.7.
Program P6.7
//count the number of characters and blanks in the input line
#include <stdio.h>
int main() {
char ch;
int numChars = 0;
int numBlanks = 0;
printf("Type some data and press 'Enter' \n");
while ((ch = getchar()) != '\n') { // repeat as long as ch is not \n
numChars++;
// add 1 to numChars
if (ch == ' ') numBlanks++; // add 1 if ch is blank
}
printf("\nThe number of characters is %d \n", numChars);
printf("The number of blanks is %d \n", numBlanks);
}
Here is a sample run:
Type some data and press 'Enter'
One moment in time
The number of characters is 18
The number of blanks is 3
The if statement tests the condition ch == ' '; if it is true (that is, ch contains a blank),
numBlanks is incremented by 1. If it is false, numBlanks is not incremented; control would
normally go to the next statement within the loop but there is none (the if is the last statement).
Therefore, control goes back to the top of the while loop, where another character is read and
tested for \n.
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