C++ 代码

#include <iostream>
#include <cstring>
#include <algorithm>
#include <vector> //5 6  8 9 9 10 11
using namespace std;
const int N = 1e6;
int n,re,ans;
int main()
{
    scanf("%d", &n);
    vector<int>a;
    vector<int>c;
    int b; 
    while(cin>>b) 
    {
        a.push_back(b);
    }
    sort(a.begin(),a.end());//排序
    for (int i = a[0]; i <=a.back(); i ++ )
    {
        c.push_back(i);
    }
    // for (int i = 0; i < a.size(); i ++ ) printf("%d\n",a[i]);
    for (int i = 0; i < a.size(); i ++ )
    {
        if(a[i]==a[i+1]) 
        {
            a.erase(a.begin() + i); 
            re=a[i];
            // printf("%d\n",a[i]);
            break;
        }

    }
    for (int i = 0; i <=a.back(); i ++ )
    {
        if(a[i]!=c[i])
        {
            ans=c[i];
            printf("%d ",c[i]);
            break;
        }
    }
    printf("%d",re);
    return 0;
}