Submission #518473

#	Time	Username	Problem	Language	Result	Execution time	Memory
518473		julian33	Boat (APIO16_boat)	C++14	9 / 100	1766 ms	4388 KiB

boat

#include <bits/stdc++.h>

using namespace std;

#ifdef LOCAL
#define deb(...) logger(#__VA_ARGS__, __VA_ARGS__)
template<typename ...Args>
void logger(string vars, Args&&... values) {
    cerr<<vars<<" = ";
    string delim="";
    (...,(cerr<<delim<<values,delim=", "));
    cerr<<"\n";
}
#else
#define deb(...) logger(#__VA_ARGS__, __VA_ARGS__)
template<typename ...Args>
void logger(string vars, Args&&... values) {}
#endif

#define pb push_back
#define sz(x) (int)(x.size())
typedef long long ll;
typedef pair<int,int> pii;
typedef pair<ll,ll> pll;
template<typename T> inline void maxa(T& a,T b){a=max(a,b);}
template<typename T> inline void mina(T& a,T b){a=min(a,b);} 
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());

const int mxN=2e5+5; //make sure this is right
const int mod=1e9+7;

struct RANK{
    vector<int> all;
    int get(int x){return lower_bound(all.begin(),all.end(),x)-all.begin()+1;}
    void add(int x){all.pb(x);}
    void fix(){
        sort(all.begin(),all.end());
        all.resize(unique(all.begin(),all.end())-all.begin());
    }  
} rnk;

ll dp[505][1005],a[505],b[505];

int main(){
    cin.sync_with_stdio(0);
    cin.tie(0); cout.tie(0);

    #ifdef LOCAL
        freopen("input.txt","r",stdin);
        freopen("output.txt","w",stdout);
    #endif

    rnk.add(1);
    int n; cin>>n;
    for(int i=1;i<=n;i++){
        cin>>a[i]>>b[i];
        rnk.add(a[i]);
        rnk.add(b[i]);
        rnk.add(b[i]+1);
    }
    rnk.fix();
    dp[0][1]=1;
    for(int i=1;i<=n;i++){
        int A=a[i]; int B=b[i];
        for(int j=1;j<=sz(rnk.all);j++){
            ll ways=min(B,rnk.all[j-1]-1)-max(A,j==1?1:rnk.all[j-2])+1;
            maxa(ways,0LL);
            dp[i][j]=dp[i-1][j];
            for(int k=j-1;k>=1;k--){
                dp[i][j]+=(dp[i-1][k]*ways)%mod;
                dp[i][j]%=mod;
            }
        }
    }
    ll ans=0;
    for(int i=2;i<=sz(rnk.all);i++)
        ans=(ans+dp[n][i])%mod;
    cout<<ans<<"\n";
}

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