oj.uz

Submission #360122

# Submission time Handle Problem Language Result Execution time Memory
360122 2021-01-27T13:25:52 Z LucaDantas Skyscraper (JOI16_skyscraper) C++17
15 / 100
 1 ms 876 KB 
#include<bits/stdc++.h>
using namespace std;

constexpr int maxn = 105, maxl = 1005, mod = 1000000007;

int dp[maxn][maxn][maxl][3];

// dp(i, j, k, z) | i == current position | j == number of components
// k == value of the perm | z == number of ends filled

void add(int& a, long long b) {
	b %= mod;
	a += b;
	if(a >= mod) a -= mod;
}

int main() {
	int n, L; scanf("%d %d", &n, &L);
	vector<int> a(n);
	for(int& x : a)
		scanf("%d", &x);
	sort(a.begin(), a.end());

	for(int i = 0; i <= L; i++)
		dp[0][0][i][0] = 1;

	for(int i = 0; i < n; i++) {
		int dif = a[i] - (i?a[i-1]:0);
		for(int j = 0; j <= i; j++) {
			for(int k = 0; k <= L; k++) {
				for(int z = 0; z <= min(j, 2); z++) {
					int val = k + dif * (2*j - z);
					// printf("%d\n", val);
					if(val > L) continue;
					// Merge a component with one of the ends
					if(j && z != 2)
						add(dp[i+1][j][val][z+1], 1ll * dp[i][j][k][z] * (2-z));
					// Create a new component one of the ends
					if(z != 2)
						add(dp[i+1][j+1][val][z+1], 1ll * dp[i][j][k][z] * (2-z));
					// Merge two components in the middle
					if(j >= 2)
						add(dp[i+1][j-1][val][z], 1ll * dp[i][j][k][z] * (j-1));
					// Append to an existing component
					if(j)
						add(dp[i+1][j][val][z], 1ll * dp[i][j][k][z] * (2*j - z));
					// Create a new component in the middle
					add(dp[i+1][j+1][val][z], 1ll * dp[i][j][k][z] * (j+1-z));
				}
			}
		}
	}

	printf("%d\n", dp[n][1][L][2]);
}

Compilation message

skyscraper.cpp: In function 'int main()':
skyscraper.cpp:18:17: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   18 |  int n, L; scanf("%d %d", &n, &L);
      |            ~~~~~^~~~~~~~~~~~~~~~~
skyscraper.cpp:21:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   21 |   scanf("%d", &x);
      |   ~~~~~^~~~~~~~~~

Subtask #1
0 / 5.0

# Verdict Execution time Memory Grader output
1 Incorrect 1 ms 364 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #2
15.0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 748 KB Output is correct
2 Correct 1 ms 748 KB Output is correct
3 Correct 1 ms 876 KB Output is correct
4 Correct 1 ms 748 KB Output is correct
5 Correct 1 ms 748 KB Output is correct
6 Correct 1 ms 876 KB Output is correct
7 Correct 1 ms 748 KB Output is correct
8 Correct 1 ms 876 KB Output is correct
9 Correct 1 ms 876 KB Output is correct
10 Correct 1 ms 748 KB Output is correct

Subtask #3
0 / 80.0

# Verdict Execution time Memory Grader output
1 Incorrect 1 ms 364 KB Output isn't correct
2 Halted 0 ms 0 KB -