poj 2777 Count Color

#include<iostream>
#include<cstdio>
#include<cstring>
#include<algorithm>
using namespace std;
#define N 100010
struct node{
int l;
int r;
int c;
}anode[4*N];
int vis[33],ans;
void bulid(int l,int r,int n){
anode
.l=l;
anode
.r=r;
anode
.c=1;
int mid=(l+r)>>1;
if(l==r)
return;
bulid(l,mid,2*n);
bulid(mid+1,r,2*n+1);
}
void update(int l,int r,int n,int c){
if(anode
.l==l&&anode
.r==r){
anode
.c=c;
return;
}
if(anode
.c>0){
anode[2*n].c=anode[2*n+1].c=anode
.c;
anode
.c=0;
}
int mid=(anode
.l+anode
.r)>>1;
if(r<=mid)
update(l,r,2*n,c);
else if(l>mid)
update(l,r,2*n+1,c);
else{
update(l,mid,2*n,c);
update(mid+1,r,2*n+1,c);
}
}
void query(int l,int r,int n){
if(anode
.c!=0){
if(!vis[anode
.c]){
ans++;
vis[anode
.c]=1;
}
return;
}
int mid=(anode
.l+anode
.r)>>1;
if(r<=mid)
query(l,r,2*n);
else if(l>mid)
query(l,r,2*n+1);
else{
query(l,mid,2*n);
query(mid+1,r,2*n+1);
}
}
int main(){
int L,T,O,a,b,c;
char str;
while(~scanf("%d %d %d",&L,&T,&O)){
bulid(1,L,1);
while(O--){
getchar();
scanf("%c",&str);
if(str=='C'){
scanf("%d %d %d",&a,&b,&c);
if(a>b)
swap(a,b);
update(a,b,1,c);
}
else{
scanf("%d %d",&a,&b);
if(a>b)
swap(a,b);
ans=0;
memset(vis,0,sizeof(vis));
query(a,b,1);
printf("%d\n",ans);
}
}
}
return 0;
}