1function main(input) {
2 //Enter your code here
3 var data = input.split('\n');
4 var firstLine = data[0].split(' ');
5 var len = firstLine[0];
6 //process.stdout.write('length:'+len);
7 var toFind = firstLine[1];
8 //process.stdout.write('toFind:'+toFind);
9 //process.stdout.write('\n');
10 var arr = data[1].split(' ');
11 //process.stdout.write(arr);
12 for(var i=len-1;i>=0;i--) {
13 if(arr[i] == toFind){
14 process.stdout.write(i+1);
15 return;
16 }
17 }
18 process.stdout.write(-1);
19}
20