Submission #1165132

#	Time	Username	Problem	Language	Result	Execution time	Memory
1165132		SmuggingSpun	Boat (APIO16_boat)	C++20	31 / 100	1104 ms	46904 KiB

boat

#include<bits/stdc++.h>
#define taskname "A"
using namespace std;
const int lim = 505;
const int mod = 1e9 + 7;
void add(int& a, int b){
    if((a += b) >= mod){
        a -= mod;
    }
}
int n, a[lim], b[lim];
namespace sub12{
    const int LIM = 1e9 + 5;
    map<int, int>bit;
    void update(int p, int x){
        for(; p < LIM; p += p & -p){
            add(bit[p], x);
        }
    }
    int get(int p){
        int ans = 0;
        for(; p > 0; p -= p & -p){
            auto it = bit.find(p);
            if(it != bit.end()){
                add(ans, it->second);
            }
        }
        return ans;
    }
    void solve(){
        update(1, 1);
        for(int i = 1; i <= n; i++){
            for(int j = b[i]; j >= a[i]; j--){
                update(j + 1, get(j));
            }
        }
        cout << (get(LIM - 1) + mod - 1) % mod;
    }
}
int main(){
	ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
	if(fopen(taskname".inp", "r")){
		freopen(taskname".inp", "r", stdin);
	}
    cin >> n;
    for(int i = 1; i <= n; i++){
        cin >> a[i] >> b[i];
    }
    int sum = 0;
    for(int i = 1; i <= n; i++){
        if((sum += b[i] - a[i]) > 1000000){
            break;
        }
    }
    if(sum < 1000001){
        sub12::solve();
    }
}

Compilation message (stderr)

boat.cpp: In function 'int main()':
boat.cpp:43:24: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   43 |                 freopen(taskname".inp", "r", stdin);
      |                 ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~

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