1.5.3 Line Counting

Program

#include <stdio.h>
static const char *_input = "line one\nline two\n";
static int _pos = 0;
#define getchar() (_input[_pos] ? (int)(unsigned char)_input[_pos++] : EOF)

/* count lines in input */
int main() {
    int c, nl;
    nl = 0;
    while ((c = getchar()) != EOF)
        if (c == '\n')
            ++nl;
    printf("%d\n", nl);
}

Explanation

This Program counts input lines. The program does that counting by setting a variable nl to 0 in the beginning. As the program one character at a time in the while loop ((c = getchar()) != EOF) till the EOF. If the character is newline character ‘n’ the number of lines variable is incremented, ++nl. At the end, the number of lines, nl, is printed.

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This document was updated on 25 May of 26

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