le

#include <stdio.h>

/* le:  output every line of input prefixed with "le" */
int main()
{
    int c;
    int d = 0;

    printf("le ");
    while ((c = getchar()) != EOF) {
        putchar(c);
        if (c == '\n' && (d = getchar()) != EOF)
            printf("le ");
        if (d) {
            ungetc(d, stdin);
            d = 0;
        }
    }
    return 0;
}