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 <fstream>
#include <cstdio>
#include <cmath>
#include <vector>
#include <cstring>
#include <string>
#include <set>
#include <map>
#include <stack>
#include <queue>
#include <algorithm>
using namespace std;
 
#define REP(i,n) for(int i=0; i<n; ++i)
#define FOR(i,a,b) for(int i=a; i<=b; ++i)
#define FORR(i,a,b) for (int i=a; i>=b; --i)
#define pi M_PI
 
typedef long long ll;
typedef vector<int> VI;
typedef vector<ll> VL;
typedef vector<VI> VVI;
typedef pair<int,int> P;
typedef pair<ll,ll> PL;

const int N = 1270;

int main() {
    int n, m, r, q;
    while (cin >> n >> m && n){
        VVI a(m,VI(N));
        cin >> r;
        while (r--){
            int t, x, y, s;
            cin >> t >> x >> y >> s;
            y--;
            if (s == 0) a[y][t]--;
            else a[y][t]++;
        }
        REP(i,m) REP(j,N-1) a[i][j+1] += a[i][j];
        cin >> q;
        while (q--){
            int ans = 0;
            int ts, te, x;
            cin >> ts >> te >> x;
            x--;
            FOR(i,ts,te-1){
                if (a[x][i] > 0) ans++;
            }
            cout << ans << endl;
        }
    }
    return 0;
}

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

int N,M,r,q;
vector <int> t,n,m,s;

int main() {

  while(1) {
    cin >> N >> M;
    if(N == 0 && M == 0 ) break;
    
    cin >> r;
  
    t.resize(r);
    n.resize(r);
    m.resize(r);
    s.resize(r);
  
    for(int i=0;i<r;i++) {
      cin >> t[i] >> n[i] >> m[i] >>s[i];
    }

    vector <int> s2;
    cin >> q;
    s2.resize(N+1);
    int ts,te,st;
    for(int ques=0;ques<q;ques++) {
    
      cin >> ts >> te >> st;
    
      for(int i=0;i<=N;i++) s2[i] = 0;

      int count = 0, time = ts;
      int start;
      for(start=0;start<r;start++) {
	if(t[start] >=ts) break;
	if(m[start] == st) s2[n[start]] = s[start];
      }
      start--;
    
      while(1) {
      
	if(time == te) break;

	if(t[start+1] <= time) start++; 
	if(m[start] == st) s2[n[start]] = s[start];

	int sum = 0;
	for(int i=1;i<=N;i++) sum += s2[i];
	if(sum != 0) count++;

	time++;
      }

      cout << count << endl;

    }
  }
  return 0;

}

C++: #include<iostream>
#include<map>
#include<vector>
using namespace std;
typedef pair<int,int> P;
typedef pair<P,P> PP;
int main(){
  int N,M;
  int r;
  while(cin>>N>>M,N||M){
    cin>>r;
    int t,n,m,s;
      vector<PP> v(r);
    for(int i=0;i<r;i++){
      cin>>t>>n>>m>>s;
      v[i]=PP(P(t,n),P(m,s));
    }
    int q;
    cin>>q;
    for(int i=0;i<q;i++){
      int s,e,h,ans=0,cnt=0;
      cin>>s>>e>>h;
      int st;
      for(int j=0;j<r;j++){
	if(v[j].second.first==h){
	  if(v[j].second.second==1){
	    if(cnt==0){
	      st=v[j].first.first;
	      if(st<s){
		st=s;
	      }
	  
	    }
	    cnt++;
	  }else{
	    cnt--;
	    int end=v[j].first.first;
	    if(v[j].first.first>e){
	      end=e;
	    }
	    if(cnt==0){
	      ans+=max(end-st,0);
	    }

	  }
	}

      }
      cout<<ans<<endl;
    }
  }

  return 0;
}

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

using namespace std;
typedef pair<int, int> pii;

int main(){

    while(1){
        int N, M;
        cin>> N>> M;
        if(!(N||M)) break;
        int r;
        cin>> r;

        int a[M][2000];
        for(int i=0; i<M; i++){
            for(int j=0; j<2000; j++){
                a[i][j]=0;
            }
        }
        for(int i=0; i<r; i++){
            int t, n, m, s;
            cin>> t>> n>> m>> s;
            n--; m--;
            if(s){
                a[m][t]+=1;
            }else{
                a[m][t+1]-=1;
            }
        }
        for(int i=0; i<M; i++){
            for(int j=1; j<2000; j++){
                a[i][j]+=a[i][j-1];
            }
        }

        int Q;
        cin>> Q;
        for(int i=0; i<Q; i++){
            int s, e, m;
            cin>> s>> e>> m;
            m--;
            int k=0;
            for(int j=s; j<=e; j++){
                k+=(a[m][j]>0);
            }
            cout<< k-2<< endl;
        }
    }

    return 0;
}

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

using namespace std;
typedef pair<int, int> pii;

int main(){
	while(true){
		int N, M;
		cin >> N >> M;
		if(N == 0 && M == 0){ break; }
		int r;
		cin >> r;
		vector< vector<pii> > logs(M + 1);
		for(int i = 0; i < r; ++i){
			int t, n, m, s;
			cin >> t >> n >> m >> s;
			logs[m].push_back(pii(t, s * 2 - 1));
		}
		int q;
		cin >> q;
		for(int i = 0; i < q; ++i){
			int ts, te, m;
			cin >> ts >> te >> m;
			vector<int> integral(1300);
			for(int j = 0; j < logs[m].size(); ++j){
				integral[logs[m][j].first] += logs[m][j].second;
			}
			for(int j = 0, s = 0; j < 1300; ++j){
				s += integral[j];
				integral[j] = s;
			}
			int answer = 0;
			for(int j = ts; j < te; ++j){
				answer += min(integral[j], 1);
			}
			cout << answer << endl;
		}
	}
	return 0;
}