# |
Submission time |
Handle |
Problem |
Language |
Result |
Execution time |
Memory |
1002863 |
2024-06-19T20:53:54 Z |
MarwenElarbi |
Nafta (COI15_nafta) |
C++17 |
|
1000 ms |
28492 KB |
#include <bits/stdc++.h>
using namespace std;
#define fi first
#define se second
#define ll long long
#define pb push_back
#define ii pair<int,int>
const int nax=2e3+5;
char grid[nax][nax];
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
int arx[4]={1,-1,0,0};
int ary[4]={0,0,1,-1};
int segtree[4*nax];
int lazy[nax*4];
bool vis[nax][nax];
vector<int> dp(nax);
vector<bool> v(nax);
struct point{
int x,type,upd,sum;
bool operator<(point &o) const{
if(o.x!=x) return x<o.x;
else return type<o.type;
}
};
vector<point> sweep;
void build(int pos,int l,int r){
if(l==r){
segtree[pos]=dp[l];
return;
}
int mid=(r+l)/2;
build(pos*2+1,l,mid);
build(pos*2+2,mid+1,r);
segtree[pos]=max(segtree[pos*2+1],segtree[pos*2+2]);
return;
}
void propagate(int pos){
if(lazy[pos]!=0){
lazy[pos*2+1]+=lazy[pos];
lazy[pos*2+2]+=lazy[pos];
segtree[pos*2+1]+=lazy[pos];
segtree[pos*2+2]+=lazy[pos];
}
lazy[pos]=0;
}
void update(int pos,int l,int r,int left,int right,int value){
if(l>r||l>right||r<left) return;
if(l>=left&&r<=right){
segtree[pos]+=value;
lazy[pos]+=value;
return;
}
int mid=(r+l)/2;
propagate(pos);
update(pos*2+1,l,mid,left,right,value);
update(pos*2+2,mid+1,r,left,right,value);
segtree[pos]=max(segtree[pos*2+1],segtree[pos*2+2]);
return;
}
int query(int pos,int l,int r,int left,int right){
if(l>r||l>right||r<left) return -1e9;
if(l>=left&&r<=right) return segtree[pos];
int mid=(r+l)/2;
propagate(pos);
return max(query(pos*2+1,l,mid,left,right),query(pos*2+2,mid+1,r,left,right));
}
int n,m;
bool safe(int x,int y){
return x>0&&y>0&&x<=n&&y<=m&&!vis[x][y]&&grid[x][y]!='.';
}
int mx,mn;
int cur=0;
void dfs(int x,int y){
vis[x][y]=true;
mn=min(mn,y);
mx=max(mx,y);
cur+=(grid[x][y]-'0');
for (int i = 0; i < 4; ++i)
{
int nex=x+arx[i];
int ney=y+ary[i];
if(safe(nex,ney)){
dfs(nex,ney);
}
}
}
int main(){
cin>>n>>m;
dp.resize(m+1,0);
for (int i = 1; i <= n; ++i)
{
for (int j = 1; j <= m; ++j)
{
cin>>grid[i][j];
}
}
int cnt=0;
for (int i = 1; i <= n; ++i)
{
for (int j = 1; j <= m; ++j)
{
if(vis[i][j]||grid[i][j]=='.') continue;
mn=j;
mx=j;
cur=0;
dfs(i,j);
sweep.pb({mn,0,mn-1,cur});
sweep.pb({mx,2,mn-1,cur});
}
}
for (int i = 0; i < m; ++i) sweep.pb({i+1,1,-1,0});
sort(sweep.begin(),sweep.end());
for (int k = 0; k < m; ++k)
{
build(0,0,m);
memset(lazy,0,sizeof lazy);
//cout <<query(0,0,m,0,0)<<endl;
int ans=0;
for (int j = 0; j < sweep.size(); ++j)
{
auto cur=sweep[j];
//cout <<k<<" "<<cur.x<<" "<<cur.type<<" "<<cur.upd<<" "<<cur.sum<<endl;
//cout <<query(0,0,m,0,0)<<endl;
if(cur.type==0){
//cout <<"he"<<endl;
//cout <<cur.upd<<" "<<cur.sum<<endl;
update(0,0,m,0,cur.upd,cur.sum);
}else if(cur.type==1){
if(cur.x<=k) continue;
//cout <<query(0,0,m,0,cur.x)<<endl;
dp[cur.x]=query(0,0,m,0,cur.x-1);
ans=max(ans,dp[cur.x]);
}else{
update(0,0,m,0,cur.upd,-cur.sum);
}//cout <<query(0,0,m,0,0)<<endl;
}//cout <<endl;
/*for (int i = 0; i <= m; ++i)
{
cout <<dp[i]<<" ";
}cout <<endl;*/
cout <<ans<<endl;
}
}
Compilation message
nafta.cpp: In function 'int main()':
nafta.cpp:119:27: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<point>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
119 | for (int j = 0; j < sweep.size(); ++j)
| ~~^~~~~~~~~~~~~~
nafta.cpp:97:9: warning: unused variable 'cnt' [-Wunused-variable]
97 | int cnt=0;
| ^~~
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
2 ms |
604 KB |
Output is correct |
2 |
Correct |
1 ms |
604 KB |
Output is correct |
3 |
Correct |
0 ms |
604 KB |
Output is correct |
4 |
Correct |
2 ms |
604 KB |
Output is correct |
5 |
Correct |
1 ms |
604 KB |
Output is correct |
6 |
Correct |
1 ms |
604 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
2 ms |
604 KB |
Output is correct |
2 |
Correct |
1 ms |
604 KB |
Output is correct |
3 |
Correct |
0 ms |
604 KB |
Output is correct |
4 |
Correct |
2 ms |
604 KB |
Output is correct |
5 |
Correct |
1 ms |
604 KB |
Output is correct |
6 |
Correct |
1 ms |
604 KB |
Output is correct |
7 |
Correct |
393 ms |
2256 KB |
Output is correct |
8 |
Correct |
216 ms |
2004 KB |
Output is correct |
9 |
Correct |
30 ms |
2904 KB |
Output is correct |
10 |
Correct |
299 ms |
2004 KB |
Output is correct |
11 |
Correct |
76 ms |
1880 KB |
Output is correct |
12 |
Correct |
28 ms |
1624 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
2 ms |
604 KB |
Output is correct |
2 |
Correct |
1 ms |
604 KB |
Output is correct |
3 |
Correct |
0 ms |
604 KB |
Output is correct |
4 |
Correct |
2 ms |
604 KB |
Output is correct |
5 |
Correct |
1 ms |
604 KB |
Output is correct |
6 |
Correct |
1 ms |
604 KB |
Output is correct |
7 |
Correct |
393 ms |
2256 KB |
Output is correct |
8 |
Correct |
216 ms |
2004 KB |
Output is correct |
9 |
Correct |
30 ms |
2904 KB |
Output is correct |
10 |
Correct |
299 ms |
2004 KB |
Output is correct |
11 |
Correct |
76 ms |
1880 KB |
Output is correct |
12 |
Correct |
28 ms |
1624 KB |
Output is correct |
13 |
Execution timed out |
1012 ms |
28492 KB |
Time limit exceeded |
14 |
Halted |
0 ms |
0 KB |
- |