程序代码：

#include <cstdio>
#include <algorithm>
using namespace std;
int main() {
    int MinF=1e9,MinE=1e9;
    int a;
    int b[1000],i=0;
    while(scanf("%d",&a)) {
        if(a==0)
            break;
        b[i++]=a;
    }
    sort(b,b+i);
    printf("%d",b[1]);
    return 0;
}

程序代码：

#include <iostream>
#include <limits>

int main( void )
{
    unsigned a = std::numeric_limits<decltype(a)>::max();
    unsigned b = std::numeric_limits<decltype(b)>::max();

    for( unsigned v; std::cin>>v && v!=0; )
    {
        unsigned& t = a<b ? b : a;
        t = t<v ? t : v;
    }

    std::cout << (a<b?b:a) << std::endl;
}

程序代码：

#include <iostream>
#include<vector>
#include<set>
using namespace std;
int main()
{
    /*set<int> arr;
    int temp;
    while (cin >> temp && temp != 0)
    {
            arr.insert(temp);
    }
    set<int>::iterator it=arr.begin();
    cout << *(++it) << endl;*/

    vector<int> num;
    int min, sub, in;
    while (cin >> in && in != 0)
    {
        num.push_back(in);
    }
    min = num[0], sub = num[1];
    for (int i = 0; i < num.size(); i++)
    {
        if (num[i] < min)
        {
            sub = min;
            min = num[i];
        }
    }
    cout << sub;
}