oj.uz

Submission #30772

# Submission time Handle Problem Language Result Execution time Memory
30772 2017-07-26T12:30:47 Z PrOAhMeT Boat (APIO16_boat) C++14
0 / 100
 13 ms 4176 KB 
#include <bits/stdc++.h>
#define mp make_pair
#define pb push_back
#define pii pair<int,int>
#define LL long long
#define st first
#define nd second
#define endl '\n'
using namespace std;

const int MAXN=505;
int dp[MAXN][MAXN*2],n,a[MAXN],b[MAXN],mod=1e9+7;
vector<int> po;

int main() {

	ios_base::sync_with_stdio(0);
	cin.tie(0);
	cin>>n;
	for(int i=1;i<=n;++i) {
		cin>>a[i]>>b[i];
		po.pb(a[i]);
		po.pb(b[i]);
	}
	po.pb(0);
	sort(po.begin(),po.end());
	po.resize(unique(po.begin(),po.end())-po.begin());
	for(int i=1;i<=n;++i) {
		a[i]=lower_bound(po.begin(),po.end(),a[i])-po.begin();
		b[i]=lower_bound(po.begin(),po.end(),b[i])-po.begin();
	}
	for(int j=0;j<po.size()+2;++j)
		dp[n+1][j]=1;
	for(int i=n;i>=1;--i) {
		for(int j=1;j<po.size();++j) {
			dp[i][j]=dp[i+1][j];
			if(j<=a[i]) {
				dp[i][j]+=dp[i+1][a[i]+1];
				if(dp[i][j]>=mod)
					dp[i][j]-=mod;
			}
			for(int k=max((int)a[i]+1,j);k<=b[i];++k) {
				dp[i][j]+=(1LL*(po[k]-po[k-1])*dp[i+1][k+1])%mod;
				if(dp[i][j]>=mod)
					dp[i][j]-=mod;
				//cout<<"dd "<<i<<" "<<k<<" "<<po[k]-po[k-1]<<" "<<dp[i+1][k]<<endl;
			}
			//cout<<i<<" "<<j<<" "<<po[j]<<" "<<dp[i][j]<<" "<<a[i]<<" "<<b[i]<<endl;
		}
	}
	cout<<(dp[1][1]-1+mod)%mod<< endl;

}

Compilation message

boat.cpp: In function 'int main()':
boat.cpp:32:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int j=0;j<po.size()+2;++j)
               ^
boat.cpp:35:16: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   for(int j=1;j<po.size();++j) {
                ^

Subtask #1
0 / 9.0

# Verdict Execution time Memory Grader output
1 Incorrect 0 ms 4176 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #2
0 / 22.0

# Verdict Execution time Memory Grader output
1 Incorrect 0 ms 4176 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #3
0 / 27.0

# Verdict Execution time Memory Grader output
1 Incorrect 13 ms 4176 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #4
0 / 42.0

# Verdict Execution time Memory Grader output
1 Incorrect 0 ms 4176 KB Output isn't correct
2 Halted 0 ms 0 KB -