#include "bits/stdc++.h" using namespace std; #define print(x) cout< PI; typedef pair V; typedef vector VE; const ll mod = 100000000000; using namespace std; int main() { int n=0; int sev,one; string s; cin>>n; one=n/2; sev=n%2; one=sev>0?one-1:one; s=string(sev,'7'); s+=string(one,'1'); cout<