#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>

int putchar(int c);
int getchar(void);
int getc(FILE* stream);
int fflush(FILE *stream);
void waitkey(void);
void exit(int status);
ssize_t read(int fd, void *buf, size_t count);

int WAIT = 1;

int main(){
	int c;
	int nl = 0;
	int b  = 0;
	while((c=getchar()) != EOF){
		putchar(c);
		b++;
		if (c == '\n') nl++;
		if (nl >= 16 || (c == '\n' && b >= 512)){
			fflush(stdout);
			if(WAIT){ waitkey(); }
			nl = 0; b = 0;
		}
	}
}

void waitkey(void){
	unsigned char s[2];
	if(read(fileno(stderr), &s, 2) > 0){
		if (s[0] == 'q') exit(0);
		if (s[0] == 'r') WAIT=0;
	}
}