truncator.c

#include <stdio.h>

int main() {
    // initialize input array and int array holding offending lines
    char lines[1000];
    int offend[100] = {0};

    // initialize counter for number of offending lines and the current lineNum
    int oLines = 0;
    int lineNum = 0;

    // continuously receive lines of input until Null
    while (fgets(lines, sizeof(lines), stdin) != NULL) {
        // loop through chars in line
        for (int i = 0; lines[i] != '\0'; i ++) {
            // printf("Counter: %d, oLines: %d\n", i, oLines);
            
            // if counter is at 51, 101, etc. newline prints
            // will not print newline twice if the 51st char is a newline
            if (i > 0 && i % 50 == 0 && lines[i] != '\n') {
                printf("\n%c", lines[i]);
                // special case: count line as offending
                if (i == 50) {
                    offend[oLines] = lineNum;
                    oLines ++;
                }
            } else {
                printf("%c", lines[i]);
            }
        }
        lineNum ++; 
    }

    printf("\nTotal lines over 50 chars: %d\n", oLines);
    printf("Offending lines: ");
    
    for (int i = 0; i < oLines; i ++) {
       printf("%d, ", offend[i]);
    }

    printf("%c", '\n');
    return 0;
}