Go: package main

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

func main() {
	io := NewIo()
	defer io.Flush()
	for {
		_, M := io.NextInt(), io.NextInt()
		if M == 0 {
			break
		}
		r := io.NextInt()
		t, m, s := make([]int, r), make([]int, r), make([]int, r)
		for i := 0; i < r; i++ {
			t[i], _, m[i], s[i] = io.NextInt(), io.NextInt(), io.NextInt()-1, io.NextInt()
		}
		q := io.NextInt()
		for i := 0; i < q; i++ {
			ss, ee, mm := io.NextInt(), io.NextInt(), io.NextInt()-1
			x := make([]int, 1300)
			for j := 0; j < r; j++ {
				if m[j] == mm {
					if s[j] == 1 {
						x[t[j]]++
					} else {
						x[t[j]]--
					}
				}
			}
			for j := 1; j < 1300; j++ {
				x[j] = x[j] + x[j-1]
			}
			ans := 0
			for j := ss; j < ee; j++ {
				if x[j] > 0 {
					ans++
				}
			}
			io.Println(ans)
		}
	}
}

// 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>
#define PB push_back
#define MP make_pair
#define REP(i,n) for (int i=0;i<(n);i++)
#define FOR(i,a,b) for(int i=(a);i<(b);i++)
#define ALL(a) (a).begin(),(a).end()
#define MOD 100000
using namespace std;
typedef long long ll;
typedef unsigned long long ull;
typedef pair<int,int> P;
const int INF=1e9;
int main(){
      int n,m,r,q;
      while(cin>>n>>m&&n&&m){
            vector<P> V[10000];
            int ps[n];
            REP(i,n)ps[i]=-1;
            cin>>r;
            REP(i,r){
                  int a,b,c,d;
                  scanf("%d%d%d%d",&a,&b,&c,&d);b--;c--;
                  if(d==1)ps[b]=a;
                  else V[c].PB(MP(ps[b],a));
            }
            cin>>q;
            REP(i,q){
                  vector<P> VV;
                  int a,b,c,ans=0;
                  scanf("%d%d%d",&a,&b,&c);c--;
                  REP(i,V[c].size()){
                        P p=V[c][i];
                        if(b<p.first||p.second<a)continue;
                        if(p.first<a){
                              if(p.second<=b)VV.PB(MP(a,p.second));
                              else VV.PB(MP(a,b));
                        }else{
                              if(p.second<=b)VV.PB(MP(p.first,p.second));
                              else VV.PB(MP(p.first,b));
                        }
                  }
                  sort(ALL(VV));
                  int s,e;
                  //REP(i,VV.size())cout<<VV[i].first<<" "<<VV[i].second<<endl;
                  REP(i,VV.size()){
                        if(i==0){
                              s=VV[i].first;
                              e=VV[i].second;
                              continue;
                        }
                        if(e>=VV[i].first){
                              e=max(e,VV[i].second);
                        }else{
                              ans+=(e-s);
                              s=VV[i].first;
                              e=VV[i].second;
                        }
                        //cout<<s<<" "<<e<<endl;
                  }
                  ans+=(e-s);
                  cout<<ans<<endl;
            }
      }
}

C++: #include <bits/stdc++.h>
#define r(i,a,n) for(int i=a;i<n;i++)
using namespace std;
int main(){
	int n,p;
	while(cin>>n>>p,n){
		int q,a[10000][1261],ch[10000][1261],b,c,d,e;
		r(i,0,p)r(j,0,1261)ch[i][j]=a[i][j]=0;
		cin>>q;
		r(i,0,q){
			cin>>b>>c>>d>>e;
			if(e==1){a[d-1][b]++;ch[d-1][b]=c;}
			else{
				for(int j=b-1;j>=0;j--){
					if(ch[d-1][j]==c)break;
					a[d-1][j]++;
				}
			}
		}
		cin>>q;
		while(q--){
			int s=0;
			cin>>b>>c>>d;
			r(i,b,c)if(a[d-1][i])s++;
			cout<<s<<endl;
		}
	}
}

C++: #include <iostream>
#define NUMBER 10000
#define TIME 721
#define DIFF 540
using namespace std;

int record[NUMBER][TIME];
int rec[1000][4];
int quest[50][3];

void answer_question(int q) {
  for (int i = 0; i < q; i++) {
    int student = quest[i][2];
    int count = 0;
    for (int j = quest[i][0] - DIFF; j < quest[i][1] - DIFF; j++)
      if (record[student][j]) count++;
    cout << count << endl;
  }
}

void record_search(int r) {
  for (int i = 0; i < r; i++) {
    if (rec[i][3] == 0) continue;
    for (int j = i + 1; j < r; j++) {
      if (rec[j][1] == rec[i][1] && rec[j][2] == rec[i][2] && rec[j][3] == 0) {
	for (int k = rec[i][0] - DIFF; k < rec[j][0] - DIFF; k++) {
	  record[rec[i][2]][k] = 1;
	}
	goto label;
      }
    }
  label: ;
  }
}

int main() {
  while (true) {
    int n, m;
    cin >> n >> m;
    if (n == 0 && m == 0) return 0;

    int r, q;
    cin >> r;
    for (int i = 0; i < r; i++)
      cin >> rec[i][0] >> rec[i][1] >> rec[i][2] >> rec[i][3];

    cin >> q;
    for (int i = 0; i < q; i++)
      cin >> quest[i][0] >> quest[i][1] >> quest[i][2];

    for (int i = 0; i < r; i++)
      for (int j = 0; j < TIME; j++)
	record[i][j] = 0;
    record_search(r);
    answer_question(q);
  }
}

C++: #include <iostream>
#include <algorithm>
using namespace std;
typedef pair<int,int> P;
int N,M,R,Q;
int use[10010][1270] = {};

int main(){
	while(cin >> N >> M && N>0){
		cin >> R;
		int t,n,m,s;
		for(int i=1;i<=M;i++){
			for(int j=540;j<=1260;j++){
				use[i][j] = 0;
			}
		}
		for(int i=0;i<R;i++){
			cin >> t >> n >> m >> s;
			if(s==1) use[m][t]++;
			else use[m][t]--;
		}
		for(int i=1;i<=M;i++){
			for(int j=540;j<=1260;j++){
				use[i][j] += use[i][j-1];
			}
		}
		cin >> Q;
		int ts,te;
		for(int i=0;i<Q;i++){
			cin >> ts >> te >> m;
			int ans = 0;
			for(int j=ts;j<te;j++){
				if(use[m][j]>=1) ans++;
			}
			cout << ans << endl;
		}
	}
}