/* 
 * Very simple, very contrived example of I/O using files:
 * Read two integers from input, write to output, filenames "hardcoded"
 * as in.txt, out.txt.
 */
#include <stdio.h>

int main(int argc, char *argv[]) {

	FILE * infile = fopen("in.txt", "r");
	if (infile == NULL) {
		printf("cannot open input\n");
		return 1;
	}
	FILE * outfile = fopen("out.txt", "w");
	if (outfile == NULL) {
		printf("cannot open output\n");
		return 1;
	}
	int a, b;
	if (fscanf(infile, "%d %d", &a, &b) != 2) 
	{ 
		printf("error\n");
		return 0; 
	}
	fprintf(outfile, "%d %d\n", a, b);
	fclose(infile);
	fclose(outfile);
	return 0;
}