int main(void) {

	char username[20];
	char password[20];
	int i;


	printf("Welcome !\n\n\n");
	printf("LOGIN \n\n");

	while (i!=1) {
		if (((strcmp(username, "maths")==0) && (strcmp(password, "123a")==0)) || ((strcmp(username, "stats")==0) && (strcmp(password, "4321")==0))) {
			i=1;
		}

		else {
			printf("Username : ");
			scanf("%s",&username);
			printf("Password : ");
			scanf("%s",&password);
		}
	}
	return 0;
}