Go: package main

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

func main() {
	io := NewIo()
	defer io.Flush()
	for {
		M, T, P, R := io.NextInt(), io.NextInt(), io.NextInt(), io.NextInt()
		if M == 0 {
			break
		}
		score := make([]struct{ num, time, index int }, T)
		submit := make([][]int, T)
		for i := 0; i < T; i++ {
			score[i].index = i + 1
			submit[i] = make([]int, P)
		}

		for i := 0; i < R; i++ {
			m, t, p, j := io.NextInt(), io.NextInt()-1, io.NextInt()-1, io.NextInt()
			if j == 0 {
				score[t].num++
				score[t].time += submit[t][p]*20 + m
			} else {
				submit[t][p]++
			}
		}
		sort.SliceStable(score, func(i, j int) bool {
			return score[i].num < score[j].num || score[i].num == score[j].num && score[i].time > score[j].time
		})

		for i := T - 1; i > 0; i-- {
			io.Printf("%d", score[i].index)
			if score[i].num == score[i-1].num && score[i].time == score[i-1].time {
				io.Printf("=")
			} else {
				io.Printf(",")
			}
		}
		io.Println(score[0].index)
	}
}

// I/O template
type Io struct {
	reader    *bufio.Reader
	writer    *bufio.Writer
	tokens    []string
	nextToken int
}

func NewIo() *Io {
	return &Io{
		reader: bufio.NewReader(os.Stdin),
		writer: bufio.NewWriter(os.Stdout),
	}
}

func (io *Io) Flush() {
	err := io.writer.Flush()
	if err != nil {
		panic(err)
	}
}

func (io *Io) NextLine() string {
	var buff []byte
	for {
		line, isPrefix, err := io.reader.ReadLine()
		if err != nil {
			panic(err)
		}
		buff = append(buff, line...)
		if !isPrefix {
			break
		}
	}
	return string(buff)
}

func (io *Io) Next() string {
	for io.nextToken >= len(io.tokens) {
		line := io.NextLine()
		io.tokens = strings.Fields(line)
		io.nextToken = 0
	}
	s := io.tokens[io.nextToken]
	io.nextToken++
	return s
}

func (io *Io) NextInt() int {
	i, err := strconv.Atoi(io.Next())
	if err != nil {
		panic(err)
	}
	return i
}

func (io *Io) NextFloat() float64 {
	i, err := strconv.ParseFloat(io.Next(), 64)
	if err != nil {
		panic(err)
	}
	return i
}

func (io *Io) Println(a ...interface{}) {
	fmt.Fprintln(io.writer, a...)
}

func (io *Io) Printf(format string, a ...interface{}) {
	fmt.Fprintf(io.writer, format, a...)
}

func (io *Io) PrintIntSlice(a []int) {
	b := []interface{}{}
	for _, x := range a {
		b = append(b, x)
	}
	io.Println(b...)
}

func (io *Io) PrintStringSlice(a []string) {
	b := []interface{}{}
	for _, x := range a {
		b = append(b, x)
	}
	io.Println(b...)
}

func Log(name string, value interface{}) {
	fmt.Fprintf(os.Stderr, "%s=%+v\n", name, value)
}

func ExampleIo() {
	io := NewIo()
	defer io.Flush()
	a := make([]int, 0, 3)
	a[0], a[1], a[2] = io.NextInt(), io.NextInt(), io.NextInt()
	io.Println(a)
	io.PrintIntSlice(a)
	Log("io", a)
}

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

struct SCORE {
    int id, ans, elapsed;
    std::vector<int> miss;
    SCORE() {
        id = 0;
        ans = 0;
        elapsed = 0;
        miss.resize(10);
    }
    bool operator > (const SCORE &y) const {
        if(ans > y.ans) return true;
        if(ans < y.ans) return false;
        if(elapsed < y.elapsed) return true;
        if(elapsed > y.elapsed) return false;
        return id > y.id;
    }

    bool operator == (const SCORE &y) const {
        return (ans == y.ans) && (elapsed == y.elapsed);
    }
};

int main() {
    int M, T, P, R;
    int m, t, p, j;
    int i;

    std::vector< SCORE > player(50);
    while(std::cin >> M >> T >> P >> R) {
        if(M == 0 && T == 0 && P == 0 && R == 0) break;
        
        for(i = 0; i < T; ++i) {
            player[i].id = i + 1;
            player[i].ans = 0;
            player[i].elapsed = 0;
            for(j = 0; j < 10; ++j) {
                (player[i]).miss[j] = 0;
            }
        }
        for(i = 0; i < R; ++i) {
            std::cin >> m >> t >> p >> j;
            if(j == 0) {
                player[t - 1].ans += 1;
                player[t - 1].elapsed += (m + 20*(player[t-1]).miss[p - 1]);
            } else {
                ++(player[t - 1]).miss[p - 1];
            }
        }
        std::sort(player.begin(), player.begin() + T, std::greater<SCORE>());

        SCORE old;
        for(int i=0; i<T; ++i) {
            if(i == 0) {
                std::cout << player[i].id;
                old = player[i];
                continue;
            }

            if(old == player[i]) {
                std::cout << "=" << player[i].id;
            } else {
                std::cout << "," << player[i].id;
            }
            old = player[i];
        }
        std::cout << std::endl;
    }

}

C++: #include<bits/stdc++.h>
using namespace std;
#define PA pair<PB,int>
#define PB pair<int,int>
#define F first
#define S second

void f(int M,int T,int P,int R){
  int ans[52]={};
  int ptime[52]={};
  int ttime[52][11]={};

  while(R--){
    int m,t,p,j;
    cin>>m>>t>>p>>j;
    if(j==0){
      ans[t]++;
      ptime[t]+=m+ttime[t][p];
    }else{
      ttime[t][p]+=20;
    }
  }

  vector<PA> v;
  for(int i=1;i<T+1;i++){
    v.push_back(PA(PB(P-ans[i],ptime[i]),T-i));
  }
  sort(v.begin(),v.end());

  for(int i=0;i<T-1;i++){
    if(v[i].F.F==v[i+1].F.F&&v[i].F.S==v[i+1].F.S){
      cout<<T-v[i].S<<"=";
    }else{
      cout<<T-v[i].S<<",";
    }
  }
  cout<<T-v[T-1].S<<endl;
}


int main(){

  int M,T,P,R;
  while(true){
    cin>>M>>T>>P>>R;
    if(M==0) break;
    f(M,T,P,R);
  }
}

C++: #include <iostream>
#include <algorithm>
#include <iomanip>
#include <map>
#include <set>
#include <queue>
#include <stack>
#include <numeric>
#include <bitset>
#include <cmath>

static const int MOD = 1000000007;
using ll = long long;
using u32 = uint32_t;
using namespace std;

template<class T> constexpr T INF = ::numeric_limits<T>::max() / 32 * 15 + 208;

int main() {
    int m, t, p, r;
    while(cin >> m >> t >> p >> r, m){
        vector<array<int, 3>> v(t);
        vector<vector<int>> u(t, vector<int>(p));
        for (int i = 0; i < t; ++i) {
            v[i][2] = i+1;
        }
        for (int i = 0; i < r; ++i) {
            int a, b, c, d;
            scanf("%d%d%d%d", &a, &b, &c, &d);
            if(d == 0){
                v[b-1][0]++;
                v[b-1][1] -= a+u[b-1][c-1];
            }else {
                u[b-1][c-1] += 20;
            }
        }
        sort(v.begin(), v.end(), greater<>());
        printf("%d", v[0][2]);
        for (int i = 1; i < t; ++i) {
            if(v[i-1][0] == v[i][0] && v[i-1][1] == v[i][1]) printf("=");
            else printf(",");
            printf("%d", v[i][2]);
        }
        puts("");
    }
    return 0;
}