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

int main(){
    while(true){
        vector<pair<int, int> >term; //solved, time
        int time[100][100];
        int M, T, P, R;
        cin >> M >> T >> P >> R;

        if(M+R+P+R == 0) break;

        for(int i=0; i < 100; i++)for(int j=0; j < 100; j++) time[i][j] = 0;

        for(int i=0; i < T; i++){
            term.push_back(pair<int, int>(0, 0));
        }

        for(int i=0; i < R; i++){
            int m, t, p, j;
            cin >> m >> t >> p >> j;
            t--;
            if(j == 0){
                term[t].first = term[t].first - 1;
                term[t].second = term[t].second + m + time[t][p];
            }
            else {
                time[t][p] += 20;
            }
        }
        vector<pair<int, int> > copyTerm = term;

        sort(term.begin(), term.end());//, pairCompare);

        for(int i=0; i < term.size(); i++){
            for(int j=term.size()-1; j != -1; j--){
                if(i != 0){
                    if(term[i].first == copyTerm[j].first && term[i].second == copyTerm[j].second){
                        if(term[i-1].first != term[i].first || term[i-1].second != term[i].second){
                            cout << "," << j+1;
                            copyTerm[j].first = 100000;
                            break;
                        }
                        else {
                            cout << "=" << j+1;
                            copyTerm[j].first = 100000;
                            break;
                        }
                    }
                }
                else if(term[i].first == copyTerm[j].first && term[i].second == copyTerm[j].second){
                    cout << j+1;
                    copyTerm[j].first = 1000000;
                    break;
                }
            }
        }
        cout << endl;

        term.clear();
    }
}

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

using namespace std;

bool cmp(pair<int,pair<int,int>> lhs, pair<int,pair<int,int>> rhs){
    if (lhs.second.first!=rhs.second.first){
        return lhs.second.first>rhs.second.first;
    } else if (lhs.second.second!=rhs.second.second){
        return lhs.second.second<rhs.second.second;
    } else {
        return lhs.first>rhs.first;
    }
}

bool equiv(pair<int,int> l, pair<int,int> r){
    return (l.first == r.first && l.second == r.second);
}

int main(){
    int M,T,P,R;
    int m,t,p,j;
    while(1){
        cin >> M >> T >> P >> R;
        if (M*M+T*T+P*P+R*R==0) return 0;
        vector<pair<int,pair<int,int>>> point(T,make_pair(0,make_pair(0,0))); //??£?§£??°,????????????????¨?
        vector<vector<int>> bad(T,vector<int>(P,0));
        for(int i=0;i<T;i++){
            point[i].first=i+1;
        }
        for(int i=0;i<R;i++) {
            cin >> m >> t >> p >> j;
            if (j==0){ //??£?§£
                point[t-1].second.first++;
                point[t-1].second.second += m;
                point[t-1].second.second += 20 * bad[t-1][p-1];
            } else {
                bad[t-1][p-1]++;
            }
        }
        sort(point.begin(),point.end(),cmp);
        for(int i=0;i<T;i++) {
            if (i==0) cout << point[i].first;
            else {
                if (equiv(point[i].second,point[i-1].second)) cout << "=";
                else cout << ",";
                cout << point[i].first;
            }
        }
        cout << endl;
    }
    return 0;
}