Submission #396662

#	Time	Username	Problem	Language	Result	Execution time	Memory
396662		keta_tsimakuridze	The Kingdom of JOIOI (JOI17_joioi)	C++14	0 / 100	1 ms	332 KiB

joioi

#include<bits/stdc++.h>
#define f first
#define int long long
#define s second
using namespace std;
const int N=2e3+5,mod=1e9+7;
int t,a[N][N],r[N],l[N],mn[N],mx[N],n,m,ans;
map<int,int> fix;
vector<int> val;
string s;

bool check(int mx1){
	int diff=mx1-val[0]; 
	for(int i=1;i<=n;i++) {
		l[i]=m+1;  r[i]=0;
	}
	for(int i=1;i<=n;i++) {
		for(int j=m;j>=1;j--){
			if(a[i][j]>mx1) l[i] = j - 1;
		}
		for(int j=1;j<=m;j++){
			if(a[i][j]+diff<val.back()) r[i] = j + 1;
		}
	}
	int Mn = m,Mx = 0;
	mn[n+1] = m; mx[n+1] = m;
	for(int i=n;i>=1;i--){
		mn[i]=min(mn[i],r[i]);
		mx[i]=max(mx[i],mx[i]);
	}
	for(int i=1;i<=n;i++){
		if(r[i] > l[i]+1) return 0;
		Mn=min(Mn,l[i]);
		Mx=max(Mx,r[i]);
		if(l[i] == 0 && (mn[i]|| Mn)) return 0;
		if(r[i] == m + 1 && (mx[i]!=m+1 || Mx!=m+1)) return 0;
		
	}
	return 1;
}
void search(){	
	int l = 0,r =(int)val.size()-1;
	while(l<=r){
		int mid=(l+r)/2;
		if(check(val[mid])) { 
			ans =min(ans, (val[mid]-val[0])); 
			r=mid-1;
		}
		else l=mid+1;
	}
}
bool check2(int mn1){
	int diff=val.back()-mn1;
	for(int i=1;i<=n;i++) {
		l[i]=m+1;  r[i]=0;
	}
	for(int i=1;i<=n;i++) {
		for(int j=m;j>=1;j--){
			if(a[i][j]<mn1) l[i] = j - 1;
		}
		for(int j=1;j<=m;j++){
			if(a[i][j]-diff>val[0]) r[i] = j + 1;
		}
	}
	int Mn = m,Mx = 0;
	mn[n+1] = m; mx[n+1] = m;
	for(int i=n;i>=1;i--){
		mn[i]=min(mn[i],r[i]);
		mx[i]=max(mx[i],mx[i]);
	}
	for(int i=1;i<=n;i++){
		if(r[i] > l[i]+1) return 0;
		Mn=min(Mn,l[i]);
		Mx=max(Mx,r[i]);
		if(l[i] == 0 && (mn[i]|| Mn)) return 0;
		if(r[i] == m + 1 && (mx[i]!=m+1 || Mx!=m+1)) return 0;
		
	}
	return 1;
}
void search2(){
	int l = 0,r =(int)val.size()-1;
	while(l<=r){
		int mid=(l+r)/2; 
		if(check2(val[mid])) { 
			ans = min(ans,(-val[mid]+val.back())); 
			l=mid+1;
		}
		else r=mid-1;
	}	
}
 main(){
	// t=1;
	cin>>n>>m;
	for(int i=1;i<=n;i++){
		for(int j=1;j<=m;j++){
			cin >> a[i][j]; 
			if(!fix[a[i][j]]) val.push_back(a[i][j]);
			fix[a[i][j]]=1;
		}
	}
	sort(val.begin(),val.end());
	ans = val.back()-val[0]; 
	search();
	search2();
	for(int i=1;i<=n;i++){
		for(int j=1;j<=m/2;j++){
			swap(a[i][j],a[i][m-j+1]);
		}
	}
	search();
	search2();
	cout<<ans;
}

Compilation message (stderr)

joioi.cpp:92:7: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
   92 |  main(){
      |       ^

• Subtask 1: 0 / 15
• Subtask 2: 0 / 45
• Subtask 3: 0 / 40