求助

P1138

记录

#include <bits/stdc++.h>
using namespace std;

bool box[300000 + 10];

int main(){
    int n,k;
    cin >> n >> k;
    for(int i = 1;i <= n;i++){
        int x;
        cin >> x;
        box[x] = 1;
    }
    int pos = 0;
    for(int i = 1;i <= k;++i){
        if(!box[++pos]) --i;
    }
    cout << pos << endl;
    return 0;
}