#include <stdio.h>
#include <stdlib.h>
#include <string.h>
void main(int argc, char *argv[])
{
	FILE *f_op, *f_sv;
	char tmp, buff[60]="      del ";

	if (!(f_op=fopen(argv[1], "rt"))) exit(1);
	if (!(f_sv=fopen("tmp.tmp", "wt"))) exit(1);
	while ((tmp=fgetc(f_op))!=EOF)
	{
		if (tmp==argv[2][0]) tmp=argv[3][0];
		fputc(tmp, f_sv);
	}
	fcloseall();
	strcat(buff, argv[1]);
	system(buff);
	strcpy(buff, "move tmp.tmp ");
	strcat(buff, argv[1]);
	system(buff);
}