#include <bits/stdc++.h>
using namespace std;
int main (){
    //700000+x=(10x+7)*4
    int x=(700000-4*7)/(4*10-1);
    cout<<10*x+7;
    return 0;
}
/**************************************************************
	Problem: 1013
	User: lidongbo
	Language: C++
	Result: Accepted
	Time:3 ms
	Memory:2072 kb
****************************************************************/