Submission #518461

# Submission time Handle Problem Language Result Execution time Memory
518461 2022-01-23T21:04:57 Z julian33 Boat (APIO16_boat) C++14
0 / 100
2 ms 4172 KB
#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.fix();
    for(int i=1;i<=sz(rnk.all);i++)
        dp[0][i]=1;
    for(int i=1;i<=n;i++){
        int A=rnk.get(a[i]);
        int B=rnk.get(b[i]);
        for(int j=1;j<=sz(rnk.all);j++){
            dp[i][j]=dp[i-1][j];
            int hi=min(rnk.all[j-1]-1,B);
            int lo=max(j==1?1:rnk.all[j-2],A);
            if(lo>hi) continue;
            dp[i][j]+=(dp[i-1][j-1]*(hi-lo+1))%mod;
            dp[i][j]%=mod;
        }
    }
    ll ans=0;
    for(int i=1;i<=sz(rnk.all);i++)
        ans=(ans+dp[n][i])%mod;
    cout<<ans<<"\n";
}
# Verdict Execution time Memory Grader output
1 Incorrect 2 ms 4172 KB Output isn't correct
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Incorrect 2 ms 4172 KB Output isn't correct
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Incorrect 1 ms 840 KB Output isn't correct
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Incorrect 2 ms 4172 KB Output isn't correct
2 Halted 0 ms 0 KB -