#include<bits/stdc++.h>
using namespace std;
const int MAXN=3005;
#pragma GCC optimize("Ofast","unroll-loops","omit-frame-pointer","inline")
#pragma GCC option("arch=native","tune=native","no-zero-upper")
#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,avx2,tune=native")
int a[MAXN],d[MAXN],A[MAXN],last[MAXN],depth[MAXN],ST[MAXN],EN[MAXN],tmp;
long long dp[MAXN][MAXN],pref[MAXN],tree[4*MAXN],lazy[4*MAXN];
int a[MAXN];
void updatenode(int now,int L,int R,int val){
tree[now]=((R-L+1))*val;
lazy[now]=val;
}
void pushdown(int now,int L,int R){
if(lazy[now]==-1)return;
int mid=(L+R)/2;
updatenode(2*now,L,mid,lazy[now]);
updatenode(2*now+1,mid+1,R,lazy[now]);
lazy[now]=-1;
}
int query(int now,int L,int R,int x,int y){
if(L>=x && R<=y)return tree[now];
if(L>y || R<x)return 0;
pushdown(now,L,R);
int mid=(L+R)/2;
return query(2*now,L,mid,x,y)+query(2*now+1,mid+1,R,x,y);
}
void update(int now,int L,int R,int x,int y,int val){
if(L>y || R<x)return;
if(L>=x && R<=y){
updatenode(now,L,R,val);
return;
}
int mid=(L+R)/2;
pushdown(now,L,R);
update(2*now,L,mid,x,y,val);
update(2*now+1,mid+1,R,x,y,val);
tree[now]=tree[2*now]+tree[2*now+1];
}
int main(){
ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
int n;
cin >> n;
for(int i=1;i<=n;i++){
cin >> a[i];
pref[i]=pref[i-1]+a[i];
}
memset(lazy,-1,sizeof(lazy));
memset(dp,-1,sizeof(dp));
dp[0][0]=0;
for(int j=1;j<=n;j++){
update(1,1,n,j,n,0);
for(int i=j;i<=n;i++){
if(dp[i-1][j-1]!=-1){
long long bil;
if(dp[i-1][j-1]==0)bil=2*pref[i-1];
else bil=2*pref[i-1]-pref[dp[i-1][j-1]-1];
int ki=i,ka=n,res=-1;
while(ki<=ka){
int mid=(ki+ka)/2;
if(pref[mid]>=bil){
res=mid;
ka=mid-1;
}
else ki=mid+1;
}
if(res!=-1)update(1,1,n,res,n,i);
}
dp[i][j]=query(1,1,n,i,i);
if(dp[i][j]==0)dp[i][j]=-1;
}
}
for(int j=n;j>=1;j--){
if(dp[n][j]!=-1){
cout << j << '\n';
break;
}
}
return 0;
}
Compilation message
segments.cpp:5: warning: ignoring #pragma GCC option [-Wunknown-pragmas]
5 | #pragma GCC option("arch=native","tune=native","no-zero-upper")
|
segments.cpp:9:5: error: redefinition of 'int a [3005]'
9 | int a[MAXN];
| ^
segments.cpp:7:5: note: 'int a [3005]' previously declared here
7 | int a[MAXN],d[MAXN],A[MAXN],last[MAXN],depth[MAXN],ST[MAXN],EN[MAXN],tmp;
| ^
