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>
#define rep(i,n) for(int i=0;i<n;i++)
using namespace std;
struct S{
	int t,n,m,s;
	S(int t,int n,int m,int s):t(t),n(n),m(m),s(s){}
};
int main(){
	int r,q,t,n,m,s,ans;
	while(cin>>r>>q,r){
		vector<S> lg; cin>>r;
		rep(i,r)cin>>t>>n>>m>>s,lg.push_back(S(t,n,m,s));
		cin>>q; rep(i,q){
			cin>>s>>t>>m; n=ans=0;
			rep(i,r-1){
				if(lg[i].m==m)n+=lg[i].s?1:-1;
				if(n>0)ans+=min(lg[i+1].t,t)-max(lg[i].t,s);
			}
			cout<<ans<<endl;
		}
	}
	return 0;
}

C++: #include <cstdio>
#include <cstdlib>
#include <cmath>
#include <cstring>

#include <iostream>
#include <string>
#include <algorithm>
#include <vector>
#include <queue>
#include <stack>
#include <map>
#include <set>
#include <unordered_map>
#include <unordered_set>

#include <complex>

#include <functional>
#include <cassert>

typedef long long ll;
using namespace std;

#define debug(x) cerr << #x << " = " << (x) << endl;


#define mod 1000000007 //1e9+7(prime number)
#define INF 1000000000 //1e9
#define LLINF 2000000000000000000LL //2e18
#define SIZE 10010

bool solve(){
  int n,m,r,q;
  int rec_t[SIZE],rec_m[SIZE], rec_n[SIZE], rec_s[SIZE];
  int memo[SIZE],c[SIZE] = {};
  vector<pair<int,int> > vec[SIZE];
  
  scanf("%d%d%d",&n,&m,&r);

  if(n == 0) return false;
  
  for(int i=0;i<r;i++){
    scanf("%d%d%d%d",rec_t+i, rec_n+i, rec_m+i, rec_s+i);

    if(rec_s[i] == 1){
      if(c[rec_m[i]] == 0)
        memo[rec_m[i]] = rec_t[i];
      c[rec_m[i]]++;
    }else{
      c[rec_m[i]]--;

      if(c[rec_m[i]] == 0)
        vec[rec_m[i]].push_back({memo[rec_m[i]], rec_t[i]});
    }
  }

  scanf("%d",&q);

  for(int i=0;i<q;i++){
    int ts,te,m;
    int sum = 0;
    
    scanf("%d%d%d",&ts,&te,&m);

    for(int j=0;j<vec[m].size();j++){
      if(!(te <= vec[m][j].first || vec[m][j].second <= ts)){
        sum += min(te, vec[m][j].second) - max(ts, vec[m][j].first);
      }
    }

    printf("%d\n",sum);
  }

  return true;
}

int main(){

  while(solve());
  
  return 0;
}

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

#define MAX_M 10000+1
#define MAX_N 1000

int N, M;
int r, q;

vector< pair<int, int> > ts[MAX_M];
int cnt[MAX_M];
int from[MAX_M];
int main() {
    while (cin >> N >> M) {
        if (N == 0 && M == 0) break;
        for (int i = 0; i < MAX_M; i++) ts[i].clear();
        memset(cnt, 0, sizeof(cnt));
        memset(from, 0, sizeof(from));
        cin >> r;
        for (int i = 0; i < r; i++) {
            int t, n, m, s;
            cin >> t >> n >> m >> s;
            if (s == 1) {
                if (cnt[m] == 0) from[m] = t;
                cnt[m]++;
            } else {
                cnt[m]--;
                if (cnt[m] == 0) 
                    ts[m].push_back(make_pair(from[m], t));
            }
        }
        cin >> q;
        for (int i = 0; i < q; i++) {
            int s, e, m;
            cin >> s >> e >> m;
            int total = 0;
            for (int j = 0; j < ts[m].size(); j++) {
                if (s < ts[m][j].first) {
                    if (e <= ts[m][j].second) {
                        total += (e - ts[m][j].first);
                    } else {
                        total += (ts[m][j].second - ts[m][j].first);
                    }
                } else {
                    if (s < ts[m][j].second) {
                        if (e <= ts[m][j].second) {
                            total += (e - s);
                        } else {
                            total += (ts[m][j].second - s);
                        }
                    }
                }
                //cout << ts[m][j].first << ' ' << ts[m][j].second << endl;
            }
            cout << total << endl;
        }
    }
    return 0;
}

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

#define pb push_back
#define mp make_pair
#define MAX 10001

using namespace std;

int main(void)
{
	int n,m;
	int r,q;
	int i1,i2,i3;
	int t,PCn,STm,s;
	int ts,te;
	int time_;
	int c;

	while(1){
		cin >> n >> m;
		if(n+m==0) break;

		vector<pair<int,int> > v[MAX];

		cin >> r;
		for(i1=0;i1<r;i1++){
			cin >> t >> PCn >> STm >> s;
			v[STm].pb(mp(t,s));
		}

		cin >> q;
		for(i1=0;i1<q;i1++){
			cin >> ts >> te >> STm;
			vector<int> in(1000,0);
			time_=0;
			c=0;
			int count = 0;

			for(i2=540;i2<=te;i2++){
				if(c<v[STm].size()){
					if(v[STm][c].first==i2){
						if(v[STm][c].second==1){
							c++;
							count++;
							if(v[STm][c].first==v[STm][c-1].first) i2--;
						}
						else {
							c++;
							count--;
							if(v[STm][c].first==v[STm][c-1].first) i2--;
						}
					}
				}
				if(count>0) in[i2-540]=1;	
			}

			for(i2=ts-540;i2<te-540;i2++){
				if(in[i2]==1) time_++;
			}

			cout << time_ << endl;
		}

	}
	return 0;
}