var fs = require('fs');
var length = fs.fstatSync(process.stdin.fd).size;
var buffer = Buffer.alloc(length);
var bytesRead = fs.readSync(process.stdin.fd, buffer, 0, length, 0);
var input = buffer.toString('utf8', 0, bytesRead);

//var input="1000000000000000000";
var m=1000000007n;
// u1 = um
var n=BigInt(input);
n=(n-1n)%(m-1n)+1n;
n=(n+"").replace("n","")-0;
m=(m+"").replace("n","")-0;
var b=1;


//var chk=263119286;
while(n--) {
    b=(b*10+3)%m;
    /*if (b===chk) {
        console.log(n);
        break;
    }*/
    //console.log((s=>s.substring(s.length-9))("00000000"+b));
}
console.log(b);