ZOJ-1610 Count the Colors

#include <cstdio>
#include <iostream>
#include <vector>
#include <algorithm>
#include <cstring>
#include <queue>
#define maxn 8005
using namespace std;
typedef long long ll;

int num[maxn<<2], color[maxn], p[maxn];

void Pushdown(int n){

if(num
!= -1){
num[n<<1] = num[n<<1|1] = num
;
num
= -1;
}
}
void Update(int n, int l, int r, int L, int R, int d){

if(l == L && R == r){
num
= d;
return ;
}
Pushdown(n);
int mid = (l + r) >> 1;
if(R <= mid)
Update(n<<1, l, mid, L, R, d);
else if(L > mid)
Update(n<<1|1, mid+1, r, L, R, d);
else{
Update(n<<1, l, mid, L, mid, d);
Update(n<<1|1, mid+1, r, mid+1, R, d);
}
}
void Query(int n, int l, int r){

if(l == r){
p[l] = num
;
return ;
}
Pushdown(n);
int mid = (l + r) >> 1;
Query(n<<1, l, mid);
Query(n<<1|1, mid+1, r);
}
int main(){

//freopen("in.txt", "r", stdin);
int n;

while(scanf("%d", &n) == 1){

int a, b, c;
memset(num, -1, sizeof(num));
memset(color, 0, sizeof(color));
for(int i = 1; i <= n; i++){

scanf("%d%d%d", &a, &b, &c);
a++, b++;
if(a == b)
continue;
Update(1, 1, 8000, a, b-1, c);
}
Query(1, 1, 8000);
int i = 1;
for(; i <= 8000; i++)
if(p[i] != -1){
color[p[i]]++;
break;
}
i++;
for(; i <= 8000; i++){
if(p[i] != p[i-1] && p[i] != -1){
color[p[i]]++;
}
}
for(int i = 0; i <= 8000; i++){

if(color[i]){
printf("%d %d\n", i, color[i]);
}
}
puts("");
}
return 0;
}