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 <string>
#include <algorithm>
#include <cstring>
#include <map>
#include <queue>
#include <stack>
#include <set>
#include <functional>
#include <sstream>
#include <complex>
#include <climits>
using namespace std;

#define REP(i,a,n) for(int i=(a);i<(int)(n);i++)
#define rep(i,n) REP(i,0,n)
#define pb push_back
#define mp make_pair
#define all(x) x.begin(),x.end()
#define EPS 1e-8

typedef struct _kiroku{
	int t,n,m,s;
} kiroku;

kiroku kiro[1024];

int main(){
	int n,m,r,q,ts,te,mm;
	while(scanf("%d%d",&n,&m),n|m){
		scanf("%d",&r);
		rep(i,r)scanf("%d%d%d%d",&kiro[i].t, &kiro[i].n, &kiro[i].m, &kiro[i].s);
		
		scanf("%d",&q);
		int cnt = 0;
		rep(i,q){
			scanf("%d%d%d",&ts,&te,&mm);
			int sum = 0;
			int start = 0;
			for(int i=0; i<r; i++)if( kiro[i].m==mm ){
				if( cnt==0 ){	 //init
					start = kiro[i].t;
					cnt++;
					if( start>te ) break;
				}else{
					if( kiro[i].s==1 )cnt++;
					else              cnt--;
					if( cnt==0 ){
						//printf("%d - %d = %d\n",kiro[i].t,max(ts,start),kiro[i].t-start);
						sum += (min(te,kiro[i].t)-max(ts,start));
					}
				}
			}
			printf("%d\n",sum);
		}
	}
	return 0;
}

C++: #include<iostream>
#include<string>
#include<vector>
#include<utility>
#include<queue>
#include<algorithm>
#include<cmath>
#include<cstdio>
#include<cstring>
#include<cstdlib>
#include<map>
#include<complex>
#define INF 2147483647
#define llINF 9223372036854775807
#define pb push_back
#define mp make_pair 
#define F first
#define S second
#define ll long long

using namespace std;
int main(){
  int n,m;
  while(cin>>n>>m,n){
    short ans[m][725]={};
    int r;cin>>r;
    for(int i=0;i<r;i++){
      int t,nn,mm,s;cin>>t>>nn>>mm>>s;
      mm--;
      t-=539;
      if(s==1)
	ans[mm][t]=1;
      else{
	ans[mm][t]=-1;
      }
    }
    int q;cin>>q;
    for(int i=0;i<q;i++){
      int t,tt,mm;cin>>t>>tt>>mm;mm--;
      int ans2=0;
      t-=539;
      tt-=539;
	int cnt=0;
	int cnt2=0;
      for(int j=0;j<=724;j++){
	cnt+=ans[mm][j];
	//cout<<cnt<<endl;;
	if(cnt>0&&j<=tt&&t<=j){cnt2++;}
	else if(cnt==0&&j<=tt&&t<=j&&ans[mm][j]>0){
	  cnt2++;
	}else{
	  if(cnt2>0)
	    ans2+=cnt2-1;
	 
	  cnt2=0;
	}
      }

      cout<<ans2<<endl;
    }
  }
  return 0;
}

C++: #include <iostream>
#include <stdio.h>
#include <algorithm>
#include <vector>
#include <queue>
#include <numeric>
#include <string>
#include <string.h>
#include <map>
#include <set>
#include <functional>
#include <complex>

using namespace std;

const int INF = (1<<30) - 1;
int S[10001][1262];

int main(){
    //ios::sync_with_stdio(false);
    //cin.tie(0);
    int N, M;
    while(cin>>N>>M, N|M){
        memset(S, 0, sizeof(S));
        
        int r;
        cin >> r;
        while(r--){
            int t, n, m, s;
            cin >> t >> n >> m >> s;
            if(s)
                S[m][t]++;
            else
                S[m][t]--;
        }
        for(int i=1; i<=M; i++)
            for(int j=1; j<1262; j++)
                S[i][j] += S[i][j-1];
            
        int q;
        cin >> q;
        while(q--){
            int s, e, m;
            cin >> s >> e >> m;
            int sum = 0;
            for(int i=s; i<e; i++)
                sum += S[m][i] > 0;
            cout << sum << endl;
        }
    }
    
    return 0;
}