Submission #1226980

#	Time	Username	Problem	Language	Result	Execution time	Memory
1226980		cpdreamer	Boat (APIO16_boat)	C++20	9 / 100	2096 ms	589824 KiB

boat

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
using namespace __gnu_pbds;
using namespace std;
const long long INF = 1e17;
typedef long long ll;
const ll MOD = 1e9+7;
#define F first
#define pb push_back
#define S second
#define P pair
#define V vector
#define all(v) v.begin(), v.end()
typedef tree<int,null_type,less<int>,rb_tree_tag, tree_order_statistics_node_update> indexed_multiset;
void file() {
    freopen("input.txt","r",stdin);
    freopen("output.txt","w",stdout);
}
ll add(ll a,ll b) {
    return ((a%MOD)+(b%MOD))%MOD;
}
void solve() {
    int n;
    cin>>n;
    ll  A[n];
    ll B[n];
    V<ll>dp[n];
    for (int i=0;i<n;i++) {
        cin>>A[i]>>B[i];
    }
    for (ll i=0;i<B[0]-A[0]+1;i++) {
        dp[0].pb(i+1);
    }
    for (ll i=1;i<n;i++) {
        for (ll j=0;j<B[i]-A[i]+1;j++) {
            ll x=1;
            for (ll g=i-1;g>=0;g--) {
                if (j+A[i]<=A[g]) {
                    continue;
                }
                x=add(x,dp[g][min(B[g]-A[g],j+A[i]-1-A[g])]);
            }
            dp[i].pb(x);
        }
        for (ll j=1;j<B[i]-A[i]+1;j++) {
            dp[i][j]=add(dp[i][j],dp[i][j-1]);
        }
    }
    ll ans=0;
    for (ll i=0;i<n;i++) {
        ans=add(ans,dp[i][B[i]-A[i]]);
    }
    cout<<ans<<endl;
}

int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    //file();
    solve();
}

Compilation message (stderr)

boat.cpp: In function 'void file()':
boat.cpp:16:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   16 |     freopen("input.txt","r",stdin);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~
boat.cpp:17:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   17 |     freopen("output.txt","w",stdout);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~

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