好久没写线段树都不知道怎么写了。。。
很easy的线段树二分问题
#include<cstdio>
#include<set>
#include<queue>
#include<cstring>
#include<algorithm>
using namespace std;
typedef long long LL;
#define lson (pos<<1)
#define rson (pos<<1|1)
const int maxn = 10005;
int n,Case = 1;
char op[10];
int Hash[maxn];
int cnt;
struct In{
int op,v;
}in[maxn];
int HASH(int x){
return lower_bound(Hash,Hash + cnt,x) - Hash + 1;
}
int sum[maxn << 2];
void pushup(int pos){
sum[pos] = sum[lson] + sum[rson];
return;
}
void update(int L,int R,int m,int pos,int value){
if(L == R){
sum[pos] = value;
return;
}
int mid = (L + R) >> 1;
if(m <= mid)
update(L,mid,m,lson,value);
else
update(mid + 1,R,m,rson,value);
pushup(pos);
return;
}
int query(int L,int R,int value,int pos){
if(L == R)
return L;
int mid = (L + R) >> 1;
if(sum[lson] >= value)
return query(L,mid,value,lson);
else
return query(mid + 1,R,value - sum[lson],rson);
}
int main(){
while(scanf("%d",&n) != EOF){
printf("Case #%d:\n",Case++);
cnt = 0;
queue<int>q;
memset(sum,0,sizeof(sum));
for(int i = 0; i < n; i++){
scanf("%s",op);
if(op[0] == 'i'){
in[i].op = 1;
scanf("%d",&in[i].v);
Hash[cnt++] = in[i].v;
}
else if(op[0] == 'o')
in[i].op = 2;
else if(op[0] == 'q')
in[i].op = 3;
}
sort(Hash,Hash + cnt);
cnt = unique(Hash,Hash + cnt) - Hash;
for(int i = 0; i < n; i++){
if(in[i].op == 1){
int e = HASH(in[i].v);
q.push(e);
update(1,cnt,e,1,1);
}
else if(in[i].op == 2){
int e = q.front(); q.pop();
update(1,cnt,e,1,0);
}
else if(in[i].op == 3){
int f = sum[1];
int fx = f / 2 + 1;
int pos = query(1,cnt,fx,1);
printf("%d\n",Hash[pos - 1]);
}
}
}
return 0;
}
/*
10
in 1
in 2
in 3
in 4
in 5
o
q
o
q
q
*/