Go: package main

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

var maxint = 10000
var scanner = bufio.NewScanner(os.Stdin)

func nextInt() (int, error) {
	scanner.Scan()
	return strconv.Atoi(scanner.Text())
}

func main() {
	scanner.Split(bufio.ScanWords)
	arr := make([]int, 10)
	for i := range arr {
		n, _ := nextInt()
		arr[i] = n
	}

	sort.Slice(arr, func(i, j int) bool {
		return arr[i] >= arr[j]
	})

	arrStr := fmt.Sprintf("%+v", arr[0:3])
	arrStr = arrStr[1:(len(arrStr) - 1)]
	arrStr = strings.Replace(arrStr, " ", "\n", -1)
	fmt.Println(arrStr)
}

C++: #include <vector>
#include <list>
#include <map>
#include <set>
#include <deque>
#include <stack>
#include <bitset>
#include <algorithm>
#include <functional>
#include <numeric>
#include <utility>
#include <sstream>
#include <queue>
#include <iostream>
#include <iomanip>
#include <cstdio>
#include <cmath>
#include <cstdlib>
#include <cctype>
#include <string>
#include <cstring>
#include <ctime>
#include <fstream>
#include <stdio.h>

using namespace std;

//conversion
//------------------------------------------
inline int toInt(string s) {int v; istringstream sin(s);sin>>v;return v;}
template<class T> inline string toString(T x) {ostringstream sout;sout<<x;return sout.str();}

//typedef
//------------------------------------------
typedef vector<int> VI;
typedef vector<VI> VVI;
typedef vector<string> VS;
typedef pair<int, int> PII;
typedef pair<int, PII> TII;
typedef long long LL;
typedef vector<LL> VLL;

//container util

//------------------------------------------
#define ALL(a)  (a).begin(),(a).end()
#define RALL(a) (a).rbegin(), (a).rend()
#define PB push_back
#define MP make_pair
#define SZ(a) int((a).size())
#define EACH(i,c) for(typeof((c).begin()) i=(c).begin(); i!=(c).end(); ++i)
#define EXIST(s,e) ((s).find(e)!=(s).end())
#define SORT(c) sort((c).begin(),(c).end())
#define MT(a,b,c) MP(a, MP(b, c))

//repetition
//------------------------------------------
#define FOR(i,a,b) for(int i=(a);i<(b);++i)
#define REP(i,n)  FOR(i,0,n)

int main(void){
	VI v(10);
	REP(i,10)cin>>v[i];
	SORT(v);
	REP(i,3)cout << v[9-i] << endl;
	return 0;
}

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

int main() {
	int a[10];
	for(int i=0;i<10;i++)
	cin>>a[i];
	for(int j=0;j<10;j++)
	{for(int i=0;i<10-1;i++)
	{
		if(a[i]<a[i+1])
		{
			int temp;
			temp=a[i];
			a[i]=a[i+1];
			a[i+1]=temp;
		}
	}}
	for(int i=0;i<3;i++)
	cout<<a[i]<<endl;
	return 0;
}

C++: #include <iostream>
#include <array>
#include <algorithm>

int main()
{
	std::array<int, 10> high;
	for (int i = 0; i < 10; ++i)
		std::cin >> high[i];

	std::sort(high.begin(), high.end());

	std::cout << high[9] << " " << high[8] << " " << high[7] << std::endl;
}

C++: int main()
{
	int i,j;
	int rank1 = 0;
	int mountain[10] = {0};
	for (i = 0; i < 10; i++) {
		scanf_s("%d", &mountain[i]);
	}



	for (i = 0; i < 10; i++) {
		for (j = i + 1; j < 10; j++) {

			if (mountain[j] > mountain[i])
			{
				rank1 = mountain[i];
				mountain[i] = mountain[j];
				mountain[j] = rank1;
			}
		}
	}

	for (i = 0; i < 3; i++) {
		printf("%d\n", mountain[i]);

		}
	
	


    return 0;
}

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

int main() {

    vector<int> vec;
    int t;
    while(cin >> t) {
       vec.push_back(t);
    }

    sort(vec.begin(), vec.end(), greater<int>());

    for(int i = 0; i < 3; i++) {
        cout << vec[i] << endl;
    }

    return 0;
}

C++: #include <iostream>
#include <vector>
#include <algorithm>

class top3hills {
public:
    top3hills();
    // top3hills(const top3hills& old);
    // ~top3hills();
    bool Run();

private:
    bool input();
    bool calc();
    void show() const;
public:
    static const int ReadMax;
    static const int ShowMax;

private:
    std::vector<int> m_mountData;   // List of mount
    std::vector<int> m_top3hills;   // List of top3 hills
};

const int top3hills::ReadMax = 10;
const int top3hills::ShowMax = 3;

top3hills::top3hills()
{

}

bool top3hills::Run()
{
    bool status = false;

    status = input();
    if (!status) {
        std::cerr << "input falure." << std::endl;
    }
    status = calc();
    if (!status) {
        std::cerr << "calc failure." << std::endl;
    }
    show();

    return true;
}

bool top3hills::input()
{
    int mountData = 0;

    for (int i = 0; i < ReadMax; ++i) {
        if (ReadMax <= i || ReadMax < m_mountData.size()) {
            return false;
        }
        std::cin >> mountData;
        m_mountData.push_back(mountData);
    }

    return true;
}

bool top3hills::calc()
{
    // Sort mount data
    std::sort(m_mountData.begin(), m_mountData.end());

    // Reverse mount data
    std::reverse(m_mountData.begin(), m_mountData.end());

    for (int i = 0; i < ShowMax; ++i) {
        if (ShowMax <= i || ShowMax < m_top3hills.size()) {
            return false;
        }
        m_top3hills.push_back(m_mountData.at(i));
    }

    return true;
}

void top3hills::show() const
{
    for (int i = 0; i < ShowMax; ++i) {
        std::cout << m_top3hills.at(i) << std::endl;
    }
}

int main()
{
    top3hills top3;
    top3.Run();
}

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

int main()
{
	int n, i , a[10];
	n=10;
	for (i=1;i<=n;i++) cin >>a[i];
	int j,tam;
	for (i=1;i<=n-1;i++)
	 for (j=i+1;j<=n;j++)
		 if (a[i]<a[j]) { tam=a[i];a[i]=a[j];a[j]=tam;}
	cout << a[1] << endl;
	cout << a[2] << endl;
	cout << a[3] << endl;
	return 0;
}

C++: lis=[];

for i in range(10):
    h=int(input());
    lis.append(h);
    
for i in range(10):
    for j in range(10):
        if lis[i]<lis[j]:
            a=lis[i];
            lis[i]=lis[j];
            lis[j]=a;
            
for i in range(3):
    print(lis[i]);

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

int main(){
int a[10] = {1819,2003,876,2840,1723,1673,3776,2848,1592,922};
int ma=0, aa=0;

for(int j=0;j<3;j++){
for(int i=0;i<10;i++){
if(ma < a[i]){
ma = a[i];
aa = i;
}
}
cout << ma << endl;
a[aa] = 0;
}

return 0;
}

C++: #include <iostream>
using namespace std;
int M[10];

void bubbleSort(int M[], int N) {
	int flag = 1;
	while (flag) {
		flag = 0;
		for (int i = N - 1; i > 0; --i) {
			if (M[i - 1] > M[i]) {
				int t = M[i];
				M[i] = M[i - 1];
				M[i - 1] = t;
				flag = 1;
			}
		}
	}
}

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

	bubbleSort(M, 10);

	for (int i = 1; i < 4; ++i) {
		cout << M[10 - i] << " ";
	}
	cout << endl;
}

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

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

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

bool compareHeight(int v1, int v2) {
	return v2 < v1;
}

int main() {
	vector<int> HeightVec;
	int iHeight = 0;
	for (int i = 0; i < 10; i++) {
		cin >> iHeight;
		HeightVec.push_back(iHeight);
	}
	
	sort(HeightVec.begin(),HeightVec.end(),compareHeight);
	cout << HeightVec[0] << endl;
	cout << HeightVec[1] << endl;
	cout << HeightVec[2] << endl;

	return 0;
}

C++: #include <iostream>
#include <set>

using namespace std;

int main(void){
	set<int, greater<int> > nums;
	for (int i=0; i<10; ++i){
		int num;
		cin >> num;
		nums.insert(num);

	}
	set<int, greater<int> >::iterator it = nums.begin();
	while (it != nums.end()){
		cout << *it << "\n";
		++it;
	}

	return 0;
}

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

int main()
{
    int t[10];
    for(int i=0;i<10;i++)cin>>t[i];
    sort(t,t+10);
    for(int j=9;j>=7;j--)cout<<t[j]<<endl;
    return 0;
}

C++: #include <iostream>
#include <vector>
#include <algorithm>

using namespace std;

int main(){
  vector<int> h(10);
  for(int i=0;i<10;++i)
	cin >> h[i];
  sort(h.begin(), h.end());
  for(int i=0;i<3;++i)
	cout << h[9-i] << endl;
  return 0;
}