Submission #125261

#	Time	Username	Problem	Language	Result	Execution time	Memory
125261		dragonslayerit	Mountains (IOI17_mountains)	C++14	70 / 100	1085 ms	27532 KiB

mountains

#include "mountains.h"
#include <vector>
#include <algorithm>
#include <cstdio>

int* base;
int memo[2001][2001];

int solve(int* begin,int* end){
  if(begin==end) return 0;
  if(memo[begin-base][end-base]!=-1) return memo[begin-base][end-base];
  int ans=1;
  std::vector<int*> sub;
  for(auto it=begin+1;it!=end;it++){
    sub.push_back(it);
  }
  std::stable_sort(sub.begin(),sub.end(),[begin](int* a,int* b){return (a-begin)*(*b-*begin)>(b-begin)*(*a-*begin);});
  std::reverse(sub.begin(),sub.end());
  int* last=end;
  for(int* it:sub){
    if(it>last) continue;
    ans+=solve(it+1,last);
    last=it;
  }
  return memo[begin-base][end-base]=std::max(ans,solve(begin+1,end));
}

int maximum_deevs(std::vector<int> y) {
  for(int i=0;i<=y.size();i++){
    for(int j=0;j<=y.size();j++){
      memo[i][j]=-1;
    }
  }
  base=y.data();
  return solve(y.data(),y.data()+y.size());
}

Compilation message (stderr)

mountains.cpp: In function 'int maximum_deevs(std::vector<int>)':
mountains.cpp:29:16: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   for(int i=0;i<=y.size();i++){
               ~^~~~~~~~~~
mountains.cpp:30:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for(int j=0;j<=y.size();j++){
                 ~^~~~~~~~~~

• Subtask 1: 20 / 20
• Subtask 2: 20 / 20
• Subtask 3: 30 / 30
• Subtask 4: 0 / 30