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#include <cstdio> #include <algorithm> #include <bits/stdc++.h> using namespace std; // a positive integer n not greater than 10^18 //所以换最多18*2个 int main() { int k; int x=8,y=9; cin>>k; if(k>36) printf("-1\n"); else { if(k%2) { cout<<y; } k/=2; while(k--) cout<<x; } return 0; }