gen.cpp

#include <iostream>

using namespace std;

int main(){
	int a,b,c,d;

	a = rand() % 9+1 ;
	b = rand() % 10;
	c = rand() % 10;
	d = rand() % 10;

	while(a == b){
		b = rand() % 10;
	}
	while(a == c||b == c){
		c = rand() % 10;
	}
	while(a == d||b == d||c == d){
		d = rand() % 10;
	}

	cout << a << b << c << d;
}