Submission #803268

#	TimeUTC-0	Username	Problem	Language	Result	Execution time	Memory
803268	2023-08-03 02:56:57	Username4132	Mountains (IOI17_mountains)	C++14	100 / 100	25 ms	14164 KiB

mountains

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#include "mountains.h"
#include <vector>
using namespace std;
using ll = long long;
#define forn(i, n) for(int i=0; i<(int)n; ++i)
#define forsn(i, s, n) for(int i=s; i<(int)n; ++i)
#define dforn(i, n) for(int i=n-1; i>=0; --i)
 
const int MAXN = 2010;
int n, dp[MAXN][MAXN];
 
bool clockwise(ll ax, ll bx, ll cx, ll ay, ll by, ll cy){
  return (ax*by + bx*cy + cx*ay - ay*bx - by*cx - cy*ax)>=0;
}
 
int maximum_deevs(vector<int> y) {
  n = y.size();
  dp[0][1]=1;
  forsn(i, 1, n){
    int lst = i-1, sum=1;
    dp[i][i+1]=1;
    dforn(j, i){
      if(clockwise(j, lst, i, y[j], y[lst], y[i])){
        sum+=dp[j+1][lst];
        lst=j;
      }
      dp[j][i+1]=max(sum+dp[j][lst], dp[j][i]);
    }
  }
  return dp[0][n];
 
 
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• Subtask 1: 20 / 20
• Subtask 2: 20 / 20
• Subtask 3: 30 / 30
• Subtask 4: 30 / 30