[백준] 14656번 : 조교는 새디스트야!! - Dart(다트)

https://www.acmicpc.net/problem/14656

import 'dart:io';
void main(){
    int? n=int.parse(stdin.readLineSync()!);
    String? s=stdin.readLineSync();
    var v=s!.split(' ').map<int>((o)=>int.parse(o));
    var count=0;
    for(var i=0;i<n;i++){
        var a=v.elementAt(i);
        if(a!=i+1) count++;
    }
    print(count);
}