HDU -- 1506 -- matrix summation <stack>

Cao oh, let me vent a mistake. I found my mistake for more than half an hour.

Really Sb...

A game time...

Touch me first

This is the simple version of the previous question =-= It is very easy to master this question.

I am suffering from this mistake. I don't want to talk about it any more.

This stack is hard to think of, but it is easy to understand, and leave a message to me =-= lack of human interaction is so lonely...

 1 #include <iostream> 2 #include <algorithm> 3 using namespace std; 4  5 typedef long long LL; 6 const int size = 100010; 7 int Left[size]; 8 int Right[size]; 9 LL h[size];10 11 int main()12 {13     int i , n;14     LL ans , area;15     while( cin >> n && n )16     {17         ans = 0;18         h[0] = h[n+1] = -1;19         for( i = 1 ; i<=n ; i++ )20         {21             cin >> h[i];22             Left[i] = Right[i] = i;23         }24         for( i = 2 ; i<=n ; i++ )25         {26             while( h[ Left[i]-1 ] >= h[i] )27             {28                 Left[i] = Left[ Left[i]-1 ];29             }30         }31         for( i = n-1 ; i>=1 ; i-- )32         {33             while( h[ Right[i]+1 ] >= h[i] )34             {35                 Right[i] = Right[ Right[i]+1 ];36             }37         }38         for( i = 1 ; i<=n ; i++ )39         {40             area = (LL) h[i] * ( Right[i] - Left[i] + 1 );41             ans = max( ans , area );42         }    43         cout << ans << endl;44     }45     return 0;46 }

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 1 #include <iostream> 2 #include <stack> 3 #include <algorithm> 4 using namespace std; 5  6 typedef long long LL; 7 const int size = 100010; 8 LL h[size]; 9 struct data10 {11     int w;12     LL h;13     data( int x , LL y )14     {15         w = x;16         h = y;17     }18 };19 stack<data>s;20 21 int main()22 {23     cin.sync_with_stdio(false);24     int n , totalW;25     LL area , ans;26     while( cin >> n && n )27     {28         for( int i = 0 ; i<n ; i++ )29         {30             cin >> h[i];31         }32         ans = h[n] = 0;33         while( !s.empty() )34             s.pop();35         for( int i = 0 ; i<=n ; i++ )36         {37             if( s.empty() || h[i] > s.top().h )38             {39                 s.push( data( 1,h[i] ) );40             }41             else if( h[i] == s.top().h )42             {43                 s.top().w ++;44             }45             else46             {47                 totalW = 0;48                 while( !s.empty() && h[i] < s.top().h )49                 {50                     totalW += s.top().w;51                     area = (LL)totalW * s.top().h;52                     ans = max( ans , area );53                     s.pop();54                 }55                 s.push( data( totalW+1,h[i] ) );56             }57         }58         cout << ans << endl;59     }60     return 0;61 }

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