右側折り返し（cの場合）

#include <stdio.h>

int main(void){
    int num=0;
    char word;
    FILE *stream;
    int maxlength=71;

    stream = fopen("../data_c.txt","r");
    while((word = getc(stream)) != EOF){
        if(word == '\n'){
            num=0;
        }else if(num > maxlength){
            printf("\n");
            num=0;
        }else{
            num++;
        }
        printf("%c",word);
    }

    return 0;
}