제출 #1138861

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
1138861		SmuggingSpun	Skyscraper (JOI16_skyscraper)	C++20	100 / 100	170 ms	91116 KiB

skyscraper

#include<bits/stdc++.h>
#define taskname "C"
using namespace std;
typedef long long ll;
const int mod = 1e9 + 7;
void add(int& a, int b){
	if((a += b) >= mod){
		a -= mod;
	}
}
int n, L;
namespace sub1{
	void solve(){
		vector<int>a(n), p(n);
		for(int& x : a){
			cin >> x;
		}
		int ans = 0;
		iota(p.begin(), p.end(), 0);
		do{
			int sum = 0;
			for(int i = 1; i < n; i++){
				sum += abs(a[p[i]] - a[p[i - 1]]);
			}
			if(sum <= L){
				ans++;
			}
		} while(next_permutation(p.begin(), p.end()));
		cout << ans;
	}
}
namespace sub2{
	int dp[1 << 14][14][101];
	void solve(){
		vector<int>a(n);
		for(int& x : a){
			cin >> x;
		}
		memset(dp, 0, sizeof(dp));
		for(int mask = 1; mask < (1 << n); mask++){
			vector<int>bit;
			for(int i = 0; i < n; i++){
				if(1 << i & mask){
					bit.emplace_back(i);
				}
			}
			if(bit.size() == 1){
				dp[mask][bit[0]][0] = 1;
			}
			else{
				for(int& i : bit){
					for(int& j : bit){
						if(i != j){
							for(int d = abs(a[i] - a[j]), k = d; k <= L; k++){
								add(dp[mask][i][k], dp[mask ^ (1 << i)][j][k - d]);
							}
						}
					}
				}
			}
		}
		int ans = 0;
		for(int i = 0; i < n; i++){
			for(int j = 0; j <= L; j++){
				add(ans, dp[(1 << n) - 1][i][j]);
			}
		}
		cout << ans;
	}
}
namespace sub3{
	const int lim = 1e2 + 5;
	const int LIM = 1e3 + 5;
	int a[lim], dp[2][lim][LIM][3];
	void solve(){
		memset(dp, 0, sizeof(dp));
		bool cur = true, pre = false;
		for(int i = dp[cur][0][0][0] = 1; i <= n; i++){
			cin >> a[i];
		}
		sort(a + 1, a + n + 1);
		if(n == 1){
			return void(cout << 1);
		}
		if(n == 2){
			return void(cout << (int(a[2] - a[1] <= L) << 1));
		}
		for(int i = 1; i < n; i++){
			swap(cur, pre);
			int delta = a[i + 1] - a[i];
			for(int j = 0; j <= i; j++){
				for(int k = 0; k <= L; k++){
					for(int t = 0; t < 3; t++){
						int after_sum = max(-1LL, ll(k) - 1LL * delta * ((j << 1) - t));
						if(j >= t && after_sum > -1 && after_sum <= L){
							dp[cur][j][k][t] = 1LL * j * dp[pre][j + 1][after_sum][t] % mod;
							if(i + j - t < n){
								add(dp[cur][j][k][t], 1LL * (j - t) * dp[pre][j - 1][after_sum][t] % mod);
								add(dp[cur][j][k][t], 1LL * ((j << 1) - t) * dp[pre][j][after_sum][t] % mod);
							}
							if(t > 0 && i + j - t <= n){
								add(dp[cur][j][k][t], 1LL * (3 - t) * dp[pre][j - 1][after_sum][t - 1] % mod);
								add(dp[cur][j][k][t], 1LL * (3 - t) * dp[pre][j][after_sum][t - 1] % mod);
							}				
						}
						else{
							dp[cur][j][k][t] = 0;
						}
					}
				}
			}
		}
		int ans = 0;
		for(int j = 1; j < 3; j++){
			for(int k = 0; k <= L; k++){
				add(ans, dp[cur][j][k][j]);
			}
		}
		cout << ans;
	}
}
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 >> L;
	if(n <= 8){
		sub1::solve();
	}
	else if(n <= 14 && L <= 100){
		sub2::solve();
	}
	else{
		sub3::solve();
	}
}

컴파일 시 표준 에러 (stderr) 메시지

skyscraper.cpp: In function 'int main()':
skyscraper.cpp:125:24: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  125 |                 freopen(taskname".inp", "r", stdin);
      |                 ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 5 / 5
• Subtask 2: 15 / 15
• Subtask 3: 80 / 80