// your code goes here
const json='{"name":"william","class":"grade1"}';
let out="";
let obj=JSON.parse(json);
let len=obj.length;
for(let x=1; x<len; x++)
{out +=x; }
console.log(out);
Ly8geW91ciBjb2RlIGdvZXMgaGVyZQpjb25zdCBqc29uPSd7Im5hbWUiOiJ3aWxsaWFtIiwiY2xhc3MiOiJncmFkZTEifSc7CmxldCBvdXQ9IiI7CmxldCBvYmo9SlNPTi5wYXJzZShqc29uKTsKbGV0IGxlbj1vYmoubGVuZ3RoOwpmb3IobGV0IHg9MTsgeDxsZW47IHgrKykKe291dCArPXg7IH0KY29uc29sZS5sb2cob3V0KTs=