oj.uz

Submission #650039

# Submission time Handle Problem Language Result Execution time Memory
650039 2022-10-12T05:36:46 Z Gromp15 Skyscraper (JOI16_skyscraper) C++17
100 / 100
 467 ms 2340 KB 
#include <bits/stdc++.h>
#define ll long long
#define ar array
using namespace std;
const int mod = 1e9+7;
void fadd(int &a, int b) {
    a += b;
    if (a >= mod) a -= mod;
}
int mul(int a, int b) {
    return (ll)a*b%mod;
}
int main() {
    cin.tie(0)->sync_with_stdio(0);
    int n, L; cin >> n >> L;
    vector<int> t(n);
    for (int &x : t) cin >> x;
    if (n == 1) {
        cout << 1 << '\n';
        return 0;
    }
    sort(t.begin(), t.end());
    vector<map<int, ar<int, 4>>> dp(n+1);
    // [# of components][total sum rn][(leftmost element filled) + (rightmost element filled)*2]
    dp[0][0][0] = 1;
    vector<int> pref(n);
    for (int i = 0; i < n; i++) pref[i] = t[i] + (i?pref[i-1]:0);
    for (int i = 0; i < n; i++) {
        vector<map<int, ar<int, 4>>> dp2(n+1);
        for (int j = 0; j <= n; j++) {
            for (const auto &[l, val] : dp[j]) {
                int need_merge = j-1;
                if (need_merge > 0 && (i+need_merge-1 >= n || (pref[i+need_merge-1] - (i?pref[i-1]:0))*2 + l > L)) {
                    continue;
                }
                for (int tp = 0; tp < 4; tp++) {
                    int num = val[tp];
                    if (!num) continue;
                    if (j > 1) { // merge
                        fadd(dp2[j-1][l+2*t[i]][tp], mul(num, j-1));
                    }
                    if (j > 0) { // add to comp
                        if (2*j-(tp&1)-(tp >> 1 & 1) > 0) fadd(dp2[j][l][tp], mul(num, 2*j-(tp&1)-(tp >> 1 & 1)));
                        if (!(tp & 1)) fadd(dp2[j][l+t[i]][tp|1], num);
                        if (!(tp >> 1 & 1)) fadd(dp2[j][l+t[i]][tp|2], num);
                    }
                    if (j+1 <= n) { // new comp
                        if (j+1-(tp&1)-(tp >> 1 & 1) > 0) fadd(dp2[j+1][l-2*t[i]][tp], mul(j+1-(tp&1)-(tp >> 1 & 1), num));
                        if (!(tp & 1)) fadd(dp2[j+1][l-t[i]][tp|1], num);
                        if (!(tp >> 1 & 1)) fadd(dp2[j+1][l-t[i]][tp|2], num);
                    }
                }
            }
        }
        swap(dp, dp2);
    }
    int ans = 0;
    for (int i = 0; i <= L; i++) { 
        fadd(ans, dp[1][i][3]);
    }
    cout << ans << '\n';
}

Subtask #1
5.0 / 5.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 212 KB Output is correct
2 Correct 0 ms 212 KB Output is correct
3 Correct 1 ms 212 KB Output is correct
4 Correct 1 ms 340 KB Output is correct
5 Correct 1 ms 340 KB Output is correct
6 Correct 1 ms 340 KB Output is correct
7 Correct 1 ms 340 KB Output is correct
8 Correct 1 ms 340 KB Output is correct
9 Correct 1 ms 340 KB Output is correct
10 Correct 1 ms 340 KB Output is correct

Subtask #2
15.0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 340 KB Output is correct
2 Correct 2 ms 340 KB Output is correct
3 Correct 1 ms 340 KB Output is correct
4 Correct 3 ms 340 KB Output is correct
5 Correct 2 ms 340 KB Output is correct
6 Correct 2 ms 340 KB Output is correct
7 Correct 2 ms 340 KB Output is correct
8 Correct 1 ms 340 KB Output is correct
9 Correct 2 ms 340 KB Output is correct
10 Correct 2 ms 340 KB Output is correct

Subtask #3
80.0 / 80.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 212 KB Output is correct
2 Correct 0 ms 212 KB Output is correct
3 Correct 1 ms 212 KB Output is correct
4 Correct 1 ms 340 KB Output is correct
5 Correct 1 ms 340 KB Output is correct
6 Correct 1 ms 340 KB Output is correct
7 Correct 1 ms 340 KB Output is correct
8 Correct 1 ms 340 KB Output is correct
9 Correct 1 ms 340 KB Output is correct
10 Correct 1 ms 340 KB Output is correct
11 Correct 1 ms 340 KB Output is correct
12 Correct 2 ms 340 KB Output is correct
13 Correct 1 ms 340 KB Output is correct
14 Correct 3 ms 340 KB Output is correct
15 Correct 2 ms 340 KB Output is correct
16 Correct 2 ms 340 KB Output is correct
17 Correct 2 ms 340 KB Output is correct
18 Correct 1 ms 340 KB Output is correct
19 Correct 2 ms 340 KB Output is correct
20 Correct 2 ms 340 KB Output is correct
21 Correct 3 ms 340 KB Output is correct
22 Correct 383 ms 1936 KB Output is correct
23 Correct 467 ms 2340 KB Output is correct
24 Correct 336 ms 1808 KB Output is correct
25 Correct 381 ms 2252 KB Output is correct
26 Correct 350 ms 2092 KB Output is correct
27 Correct 104 ms 652 KB Output is correct
28 Correct 142 ms 852 KB Output is correct
29 Correct 296 ms 1424 KB Output is correct
30 Correct 397 ms 2340 KB Output is correct