#include "elephants.h"
#include<algorithm>
using namespace std;
const int MAX_N = 150000, MAX_RTN =388;
int n,l,x[MAX_N];
int rtn;
struct st{
int sz;
int x[MAX_RTN*2],d[MAX_RTN * 2],cnt[MAX_RTN*2];
}e[MAX_RTN];
void init(int N, int L, int X[]){
n = N;
l = L;
rtn = sqrt(N);
for (int i = 0; i < N; i++)
e[i / rtn].x[e[i / rtn].sz++]=x[i] = X[i];
}
void UpdateBucket(int b){
int tpos = e[b].sz;
for (int i = e[b].sz - 1; i >= 0; i--){
while (e[b].x[tpos - 1] - e[b].x[i] > l) tpos--;
if (tpos == e[b].sz){
e[b].d[i] = e[b].x[i];
e[b].cnt[i] = 1;
}
else{
e[b].d[i] = e[b].d[tpos];
e[b].cnt[i] = e[b].cnt[tpos] + 1;
}
}
}
void Restructure(){
sort(x, x + n);
for (int i = 0; i <= rtn; i++) e[i].sz = 0;
for (int i = 0; i < n; i++)
e[i / rtn].x[e[i / rtn].sz++] = x[i];
for (int i = 0; i <= rtn; i++) UpdateBucket(i);
}
void Delete(int tx){
int b,i;
for (b = 0; b <= rtn; b++)
if (e[b].sz && tx <= e[b].x[e[b].sz - 1]) break;
if(b==rtn+1) b--;
for (i = 0; e[b].x[i] != tx; i++);
e[b].sz--;
for (; i<e[b].sz; i++) e[b].x[i] = e[b].x[i + 1];
UpdateBucket(b);
}
void Add(int tx){
int b;
for (b = 0; b <= rtn; b++)
if (e[b].sz && tx <= e[b].x[e[b].sz - 1]) break;
if (b == rtn + 1) b--;
for (int i = 0; i < e[b].sz; i++)
if (e[b].x[i]>tx) swap(e[b].x[i], tx);
e[b].x[e[b].sz++] = tx;
UpdateBucket(b);
}
int ucnt;
int update(int i, int y){
if (ucnt++%rtn == 0) Restructure();
Delete(x[i]);
Add(x[i] = y);
int ans = 0, b=-1, tx=-1, t;
while (++b <= rtn){
t = upper_bound(e[b].x, e[b].x + e[b].sz, tx) - e[b].x;
if (t == e[b].sz) continue;
ans += e[b].cnt[t];
tx = e[b].d[t] + l;
}
return ans;
}
Compilation message
elephants.cpp: In function ‘void init(int, int, int*)’:
elephants.cpp:14:14: error: ‘sqrt’ was not declared in this scope
rtn = sqrt(N);
^
