Go: package main

import (
        "fmt"
        "bufio"
        "os"
        "strconv"
)

func main() {
        fp := os.Stdin
        scanner := bufio.NewScanner(fp)
        var lst [3]int

        for scanner.Scan() {
                num, _ := strconv.Atoi(scanner.Text())
                if lst[0] < num {
                        lst[2] = lst[1]
                        lst[1] = lst[0]
                        lst[0] = num
                } else if lst[1] < num {
                        lst[2] = lst[1]
                        lst[1] = num
                } else if lst[2] < num {
                        lst[2] = num
                }
        }

        for _, i := range lst {
                fmt.Printf("%d\n", i)
        }
}

C++: #include<algorithm>
#include<functional>
#include<cmath>
#include<cstdio>
#include<cstdlib>
#include<cstring>
#include<string>
#include<sstream>
#include<iostream>
#include<iomanip>
#include<vector>
#include<list>
#include<stack>
#include<queue>
#include<map>
#include<set>
#include<bitset>
#include<climits>

#define all(c) (c).begin(), (c).end()
#define rep(i,n) for(int i=0;i<(n);i++)
#define pb(e) push_back(e)
#define mp(a, b) make_pair(a, b)
#define fr first
#define sc second

typedef unsigned long long UInt64;
typedef long long Int64;

const int INF=100000000;
int dx[4]={1,0,-1,0};
int dy[4]={0,1,0,-1};

using namespace std;

template<class _RanIt,class _Diff,class _Tmp> inline void _insertion_sort (_RanIt _Array,_Diff _Count,_Tmp)
{
	_Tmp tmp;
	for(_Diff i = 1; i < _Count; i++)
	{
		tmp = *(_Array + i);
		if( *(_Array + i - 1) > tmp)
		{
			_Diff j = i;
			do
			{
				*(_Array + j) = *(_Array + j - 1);
				j--;
			}while(j > 0 && *(_Array + j - 1) > tmp);
			*(_Array + j) = tmp;
		}
	}

}

template<class _RanIt,class _Diff,class _Tmp,class _Pr> inline void _insertion_sort (_RanIt _Array,_Diff _Count,_Tmp,_Pr _Pred)
{
	_Tmp tmp;
	for(_Diff i = 1; i < _Count; i++)
	{
		tmp = *(_Array + i);
		if( _Pred(*(_Array + i - 1) , tmp))
		{
			_Diff j = i;
			do
			{
				*(_Array + j) = *(_Array + j - 1);
				j--;
			}while(j > 0 && _Pred(*(_Array + j - 1) , tmp));
			*(_Array + j) = tmp;
		}
	}

}
	
template<class _RanIt> inline void insertion_sort(_RanIt _First,_RanIt _Last)
{
	_insertion_sort(_First,_Last - _First,*(_First));

}

template<class _RanIt,class _Pr> inline void insertion_sort(_RanIt _First,_RanIt _Last,_Pr _Pred)
{
	_insertion_sort(_First,_Last - _First,*(_First),_Pred);

}


//bubble_sort
template<class T> inline void myswap(T& a,T& b)
{
	T tmp;
	tmp = a;
	a = b;
	b = tmp;
}


template<class _RanIt,class _Diff> inline	void _bubble_sort (_RanIt _Array,_Diff _Count)
{
	for(_Diff i = 0; i < _Count; i++)
	{
		for(_Diff j = _Count - 1; j > i; j--)
		{
			if(_Array[j] < _Array[j-1])
			{
				myswap(_Array[j],_Array[j-1]);
			}

		}
	}	
}

template<class _RanIt,class _Diff,class _Pr> inline void _bubble_sort (_RanIt _Array,_Diff _Count,_Pr Pred)
{
	for(_Diff i = 0; i < _Count; i++)
	{
		for(_Diff j = _Count - 1; j > i; j--)
		{
			if(Pred(_Array[j] , _Array[j-1]))
			{
				myswap(_Array[j],_Array[j-1]);
			}

		}
	}	

}

template<class _RanIt> inline	void bubble_sort(_RanIt _First,_RanIt _Last)
{
	_bubble_sort(_First,_Last - _First);
}

template<class _RanIt,class _Pr> inline	void bubble_sort (_RanIt _First,_RanIt _Last, _Pr _Pred)
{
	_bubble_sort(_First,_Last - _First,_Pred);
}
	
int main()
{
	
	int a[10];
	rep(i,10) cin>>a[i];

	insertion_sort(a,a+10);


	cout<<a[9]<<endl;
	cout<<a[8]<<endl;
	cout<<a[7]<<endl;

	return 0;
}

C++: #include <iostream>
#include <algorithm>
using namespace std;

int main(){
  int i,data[10];
  for( i = 0; i < 10; i++ ){
    cin >> data[i];
  }

  for( i = 0; i < 10; i++ ){
    for ( int j = 0;j < 9; j++ ){
      if ( data[j] < data[j+1]) swap(data[j],data[j+1]);
    }
  }

  for( i = 0; i < 3; i++ ) cout << data[i] << endl;
  return 0;
}

C++: #include<bits/stdc++.h>

using namespace std;
typedef long long ll;

int main(){
    
    ios_base::sync_with_stdio(0);
    int a[10];
    for(int i=0;i<10;i++)   cin>>a[i];
    sort(a,a+10);
    cout<<a[9]<<endl;
    cout<<a[8]<<endl;
    cout<<a[7]<<endl;
    return 0;
}

C++: //
// Created by tac on 2016/10/27.
//

#include <cstdlib>
#include <functional>
#include <vector>
#include <iostream>

const int N_SIZE = 10000;

int main() {
    std::vector<int> v(N_SIZE);
    int n = 10;
    int s;
    for (int i = 0; i < n; ++i) {
        std::cin >> s;
        v.push_back(s);
    }
    std::sort(v.begin(), v.end(), std::greater<int>());
    for (int j = 0; j < 3; ++j) {
        std::cout << v[j] << std::endl;
    }
    return EXIT_SUCCESS;
}

C++: #include <iostream>
#include <array>
#include <algorithm>
 
int main(void) {
    std::array<u_int, 10> heights;
	//??\???
    for (u_int i = 0; i < 10; ++i) {
        std::cin >> heights[i];
    }
	//?????????
    std::sort(heights.begin(), heights.end(), std::greater<u_int>());
	//??????
    for (u_int i = 0; i < 3; ++i) {
        std::cout << heights[i] << std::endl;
    }
    return 0;
}

C++: #include <iostream>
#include <vector>
#include <algorithm>
using namespace std;

int main(){
	int n;
	vector<int> high;
	
	for(int i=0 ; i<10 ; i++){
		cin >> n;
		high.push_back( n );
	}
	
	sort( high.begin() , high.end() );

	for(int i=9 ; i>=7 ; i--){
		cout << high.at( i ) << endl;
	}

	return 0;
}

C++: #include <iostream>
#include <vector>
#include <string>
#include <algorithm>
#include<iomanip>
#include <cmath>
#include <queue>
#include <stack>
#include <map>
#include <cstdio>

using namespace std;

int main()
{
	vector<int> a(10, 0);
	for (int i = 0; i < 10; ++i)
		cin>>a[i];
	
	sort(a.begin(), a.end());
	cout<<a[9]<<endl;
	cout<<a[8]<<endl;
	cout<<a[7]<<endl;
	
	return 0;
}

C++: #include <iostream>
#include <vector>
#include <iterator>
using namespace std;

inline void make_top3(vector<int> &top3, int height) {
    for (auto it = top3.begin(); it != top3.end(); it++) {
        if (height > *it) {
            it = top3.insert(it, height);
            if (top3.size() > 3)
                top3.pop_back();
            return;
        }
    }
    if (top3.size() < 3)
        top3.push_back(height);
    return;
}

int main()
{
    int height;
    vector<int> top3;

    while (cin >> height)
        make_top3(top3, height);

    for (auto h: top3)
        cout << h << endl;

    return 0;
}

C++: #include<iostream>
using namespace std;

int main(){
	int val[3]={0};
	for(int i=0;i<10;i++){
		int a;
		cin >> a;
		if(a > val[0]){
			val[2] = val[1];
			val[1] = val[0];
			val[0] = a;
		}else if(a > val[1]){
			val[2] = val[1];
			val[1] = a;
		}
		else if(a > val[0])
			val[2] = a;
	}	
	for(int i=0;i<3;i++)
	cout << val[i] << endl;
}

C++: #include <stdio.h>
#include <string.h>
#include <stdlib.h>

#define BUFSIZ 8

int main (int ac, char **av) {
  char readline[BUFSIZ] = {0};
  int mountains[3] = {0};
  while (fgets(readline, BUFSIZ, stdin) != NULL) {
    int x = atoi(readline);
    if (mountains[0] == 0) {
      mountains[0] = x;
    } else {
      int idx = 0;
      for (idx = 0; idx < 3; idx++) {
	if (mountains[idx] < x) {
	  memmove(mountains+idx+1, mountains+idx, sizeof(int) * (2-idx));
	  mountains[idx] = x;
	  break;
	}
      }
    }
  }
  int i=0;
  for (i = 0; i < 3; i++) {
    fprintf(stdout, "%d\n", mountains[i]);
  }
      

  return 0;
}

C++: #include<iostream>
using namespace std;

int main(){
	int top[3]={0,0,0},cur;
	for (int i = 0; i < 10; i++)
	{
		cin>>cur;
		if(cur>top[0]){
			top[2]=top[1];
			top[1]=top[0];
			top[0]=cur;
		}else if(cur>top[1]){
			top[2]=top[1];
			top[1]=cur;
		}else if(cur>top[2]){
			top[2]=cur;
		}
	}
	cout<<top[0]<<endl;
	cout<<top[1]<<endl;
	cout<<top[2]<<endl;
	return 0;
}