#include <bits/stdc++.h>
using namespace std;
typedef pair<int, int> pii;
typedef long long lld;
const int MX=2010, inf=2e9;
int B[MX][MX];
int w, h;
struct node {
int val, x, y;
bool used;
};
int D[MX][MX];
int solve(){
vector<node> V;
int hi=0;
for(int i=1; i<=h; i++)
for(int j=1; j<=w; j++){
V.push_back({B[i][j], i, j, false});
hi=max(hi, B[i][j]);
}
sort(V.begin(), V.end(), [](node &a, node &b){
if(a.val==b.val)
return pii(a.x,a.y) < pii(b.x,b.y);
return a.val<b.val;
});
for(int i=0; i<h*w; i++){
node &nd=V[i];
D[nd.x][nd.y]=i;
}
int pos[MX]={}; pos[0]=w;
int mn=inf, mx=0, ans=inf, cnt=0;
for(int idx=0, nah=0; idx<h*w; idx++){
int val=V[idx].val, i=V[idx].x;
for(; i<=h; i++){
bool uptd=false;
while(pos[i]<pos[i-1] && B[i][pos[i]+1]<=val){
uptd=true;
pos[i]++;
int now=B[i][pos[i]];
mn=min(mn, now), mx=max(mx, now);
V[D[i][pos[i]]].used=true;
cnt++;
}
if(!uptd) break;
}
if(cnt==0 || cnt==w*h) continue;
while(nah<w*h-1 && V[nah+1].used) nah++;
ans=min(ans, max(mx-mn, hi-V[nah].val) );
}
return ans;
}
void flip_v(){
for(int i=1; i<=h/2; i++)
for(int j=1; j<=w; j++)
swap(B[i][j], B[h-i+1][j]);
}
void flip_h(){
for(int i=1; i<=h; i++)
for(int j=1; j<=w/2; j++)
swap(B[i][j], B[i][w-j+1]);
}
int main(){
ios::sync_with_stdio(0); cin.tie(0);
cin>>h>>w;
for(int i=1; i<=h; i++)
for(int j=1; j<=w; j++)
cin>>B[i][j];
int ans=solve();
flip_v();
ans=min(ans, solve());
flip_h();
ans=min(ans, solve());
flip_v();
ans=min(ans, solve());
cout<<ans;
return 0;
}
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
2 ms |
376 KB |
Output is correct |
2 |
Correct |
2 ms |
612 KB |
Output is correct |
3 |
Incorrect |
2 ms |
692 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
2 ms |
376 KB |
Output is correct |
2 |
Correct |
2 ms |
612 KB |
Output is correct |
3 |
Incorrect |
2 ms |
692 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
2 ms |
376 KB |
Output is correct |
2 |
Correct |
2 ms |
612 KB |
Output is correct |
3 |
Incorrect |
2 ms |
692 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |