Submission #123945

#	Time	Username	Problem	Language	Result	Execution time	Memory
123945		RafikHachana	Boat (APIO16_boat)	C++14	9 / 100	2064 ms	8388 KiB

boat

#include<bits/stdc++.h>
using namespace std;

#define mod (int)(1e9+7)

int n;
vector<int> a,b;
map<pair<int,int>,int> m;

int dp(int i,int val)
{
  //cout<<val<<endl;
  if(i==n) return (int)(val!=-1);
  if(m.find({i,val})!=m.end()) return m[{i,val}];
  int r = dp(i+1,val)%mod;
  for(int j=max(val,a[i]);j<=b[i];j++) r+=(dp(i+1,j+1))%mod;
  return m[{i,val}] = r%mod;
}

int main()
{
  cin>>n;
  a.resize(n);
  b.resize(n);
  for(int i=0;i<n;i++)
  {
    cin>>a[i]>>b[i];
  }
  cout<<dp(0,-1)%mod<<endl;
}

• Subtask 1: 9 / 9
• Subtask 2: 0 / 22
• Subtask 3: 0 / 27
• Subtask 4: 0 / 42