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 <iostream>
#include <vector>
#include <algorithm>
#include <numeric>
#include <set>
#include <map>
#include <string>
#include <stack>
#include <queue>
#include <cmath>
#include <cstdio>
#include <istream>
#include <sstream>
#include <iomanip>
using namespace std;

typedef ostringstream oss;
typedef istringstream iss;

typedef vector<bool> vi;
typedef vector< vi > vvi;

const int MIN_TIME = 540;
const int MAX_TIME = 1260;


int main(void) {
	int pcNum, stuNum;
	while (cin >> pcNum >> stuNum, pcNum) {
		vector< vvi > recs(stuNum, vvi(pcNum, vi(MAX_TIME - MIN_TIME + 1, 0)));

		int recNum, queNum;
		cin >> recNum;
		for (int ri = 0; ri < recNum; ri++) {
			int time, pc, stu, type;
			cin >> time >> pc >> stu >> type;
			pc--; stu--;
			time -= MIN_TIME;
			if (type) {
				fill(recs[stu][pc].begin() + time, recs[stu][pc].end(), 1);
			}else {
				fill(recs[stu][pc].begin() + time, recs[stu][pc].end(), 0);
			}
		}

		for (int si = 0; si < stuNum; si++) {
			for (int pi = 0; pi < pcNum; pi++) {
				for (int ti = MAX_TIME - MIN_TIME; ti >= 0; ti--) {
					recs[si][0][ti] = max(recs[si][0][ti], recs[si][pi][ti]);
				}
			}
		}

		cin >> queNum;
		for (int qi = 0; qi < queNum; qi++) {
			int start, end, stu;
			cin >> start >> end >> stu;
			stu--;
			start -= MIN_TIME; end -= MIN_TIME;

			int time = 0;
			for (int ti = start; ti < end; ti++) {
				time += recs[stu][0][ti];
			}

			cout << time << endl;
		}
	}

	return 0;
}

C++: #include<bits/stdc++.h>
using namespace std;

#define MAX 100

int main(){

  while(1){
    int N,M, r, q, time[MAX][2000] = {};
    int t, n, m, s, ts, te, temp;
    cin>>N>>M;
    if(!N&&!M)break;
    cin>>r;
    for(int i = 1; i <= r; i++){
      cin>>t>>n>>m>>s;
      if(!s){
	time[n][t+1] -= m;
      }else {
	time[n][t] += m;
      }
    }

    for(int j = 540; j <= 1260; j++){
      for(int k = 1; k <= N; k++){//cout<<time[k][j]<<" ";cout<<endl;
	time[k][j] += time[k][j-1];
      }
    }
   /* for(int j = 780; j <= 870; j++){cout<<j<<" ";
      for(int k = 1; k <= N; k++)cout<<time[k][j]<<" ";cout<<endl;
    }*/
 
    cin>>q;
    for(int i = 1; i <= q; i++){
      int ans = 0, temp = 0;
      cin>>ts>>te>>m;
      for(int j = ts; j <= te; j++){
	for(int k = 1; k <= N; k++){
	  int l = j;
	  if(time[k][j] == m){//cout<<k<<" "<<j<<" "<<m<<endl;
	    while(time[k][l] && l <= te)l++;
	    ans += l-j-1; //cout<<ans<<" "<<l<<" "<<j<<endl;
	    if(temp == j-1)ans++; 
	    j = l-1;
	    temp = j;
	    break;
	  }
	}
      }
      cout<<ans<<endl;
    }
  }

  return 0;
}

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

using namespace std;

inline int toInt(string s) { int v; istringstream sin(s); sin >> v; return v; }
inline bool cheak(int x, int y, int xMax, int yMax){ return x >= 0 && y >= 0 && xMax > x && yMax > y; }
template<class T> inline string toString(T x) { ostringstream sout; sout << x; return sout.str(); }
template<class T> inline T sqr(T x) { return x*x; }

typedef pair<int, int> P;
typedef tuple<int, int,int> T;
typedef long long ll;
typedef unsigned long long ull;

#define For(i,a,b)	for(int (i) = (a);i < (b);(i)++)
#define rep(i,n)	For(i,0,n)
#define clr(a)		memset((a), 0 ,sizeof(a))
#define mclr(a)		memset((a), -1 ,sizeof(a))
#define all(a)		(a).begin(),(a).end()
#define sz(a)		(sizeof(a))
#define Fill(a,v)	fill((int*)a,(int*)(a+(sz(a)/sz(*(a)))),v)

const int dx[4] = { -1, 0, 1, 0 }, dy[4] = { 0, 1, 0, -1 };
const int mod = 1000000007;
const int INF = 1e9;

int d[10001][2000];
int f[10001][1001];

int main()
{
	int N, M;

	while (cin >> N >> M && N){
		int r;
		cin >> r;

		clr(d); clr(f);

		rep(i, r){
			int t, n, m, s;
			cin >> t >> n >> m >> s;
			if (s == 1){
				f[m][n] = t;
			}
			else{
				For(j, f[m][n], t){
					d[m][j] = 1;
				}
			}
		}

		int q;
		cin >> q;

		rep(i, q){
			int ts, te, m;
			cin >> ts >> te >> m;
			int ans = 0;
			For(j, ts, te){
				if (d[m][j])ans++;
			}
			cout << ans << endl;
		}
	}

	return 0;
}

C++: #include<iostream>
 
using namespace std;
 
#define MMAX 10000
#define tMAX (60*24)

int main(void){
 
    int N, M;
    int r;
    int t, n, m1, s;
    int q;
    int ts, te, m2;
    int num,cnt;
    int data[MMAX+1][tMAX+1];
 
    while (cin >> N >> M){
        if (N == 0 && M == 0) break;
        for (int i = 0; i <= MMAX; i++){
            for (int j = 0; j <= tMAX; j++){
                data[i][j] = 0;
            }
        }
        cin >> r;
		
        for (int i = 0; i < r; i++){
            cin >> t >> n >> m1 >> s;
            if (s == 0) data[m1][t]--;
            else data[m1][t]++;
        }
		
        for (int i = 1; i <= M; i++){
            num = 0;
            for (int j = 0; j <= tMAX; j++){
                num += data[i][j];
                data[i][j] = num;
            }
        }
		cin>>q;
        for (int i = 0; i < q; i++){
            cin >> ts >> te >> m2;
            cnt = 0;
            for (int j = ts; j < te; j++){
                if (data[m2][j] >= 1) cnt++;
            }
            cout << cnt << endl;
			return 0;
        }
    }
    return 0;
}