// Copyright (C) 2011 Toby Thain, toby@telegraphics.com.au
// Programming Praxis problem:
// http://programmingpraxis.com/2011/03/15/look-and-say/
// NOT WRITTEN FOR CLARITY. COMMENTS COST EXTRA. NO WARRANTY.

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

#define M 1000 // limit of sequence length

int main(){
	char *p1 = malloc(M), *p2 = malloc(M), *p, *q, *t, d;
	int m, n;

	p1[0] = '1';
	p1[1] = 0;
	for(; ; t = p1, p1 = p2, p2 = t){
		for(p = p1, q = p2, n = 0; *p;){
			for(m = 1, d = *p++; *p == d; ++m, ++p)
				;
			n += 2;
			if(n >= M)
				return EXIT_SUCCESS; // buffer limit
			*q++ = m+'0';
			*q++ = d;
		}
		*q = 0;
		puts(p2);
	}
}