Submission #1284015

#	Time	Username	Problem	Language	Result	Execution time	Memory
1284015		baotoan655	Skyscraper (JOI16_skyscraper)	C++20	15 / 100	5 ms	2912 KiB

skyscraper

#include <bits/stdc++.h>
#define file(name)  if (fopen(name".inp", "r")) { freopen(name".inp", "r", stdin); freopen(name".out", "w", stdout); }
using namespace std;

const int MOD = 1e9 + 7;
inline int mul(int x, int y) {
    return (long long) x * y % MOD;
}
void ADD(int &x, int y) {
    x += y;
    if(x >= MOD) x -= MOD;
}
int n, L;
int a[105];
int dpP[105][1005][3];
int dpC[105][1005][3];

int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(0), cout.tie(0);

    file("A") else file("task");
    cin >> n >> L;
    for(int i = 1; i <= n; ++i) cin >> a[i];
    sort(a + 1, a + n + 1);
    a[n + 1] = 1e4;
    dpP[0][0][0] = 1;
    for(int i = 1; i <= n; ++i) {
        memset(dpC, 0, sizeof dpC);
        for(int j = 1; j <= i; ++j) {
            for(int k = 0; k <= L; ++k) {
                for(int m = 0; m <= 2; ++m) {
                    int diff = (2 * j - m) * (a[i + 1] - a[i]);
                    if(diff > k || i + j + 1 - m > n) continue;
                    if(j > 0) ADD(dpC[j][k][m], dpP[j - 1][k - diff][m]);
                    if(j > 0 && m > 0) ADD(dpC[j][k][m], mul(3 - m, dpP[j - 1][k - diff][m - 1]));
                    ADD(dpC[j][k][m], mul(2 * j - m, dpP[j][k - diff][m]));
                    if(m == 1) ADD(dpC[j][k][m], mul(2 * j, dpP[j][k - diff][m - 1]));
                    if(m == 2) {
                        if(i == n) ADD(dpC[j][k][m], dpP[j][k - diff][m - 1]);
                        else if(j > 1) ADD(dpC[j][k][m], mul(j - 1, dpP[j][k - diff][m - 1]));
                    }
                    if(m == 2 && i == n) ADD(dpC[j][k][m], dpP[j + 1][k - diff][m]);
                    else ADD(dpC[j][k][m], mul(j * (j + 1 - m), dpP[j + 1][k - diff][m]));
                }
            }
        }
        swap(dpP, dpC);
    }
    int ans = 0;
    for(int i = 0; i <= L; ++i) ADD(ans, dpP[1][i][2]);
    cout << ans << '\n';
    return 0;
}

Compilation message (stderr)

skyscraper.cpp: In function 'int main()':
skyscraper.cpp:2:58: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
    2 | #define file(name)  if (fopen(name".inp", "r")) { freopen(name".inp", "r", stdin); freopen(name".out", "w", stdout); }
      |                                                   ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
skyscraper.cpp:22:5: note: in expansion of macro 'file'
   22 |     file("A") else file("task");
      |     ^~~~
skyscraper.cpp:2:91: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
    2 | #define file(name)  if (fopen(name".inp", "r")) { freopen(name".inp", "r", stdin); freopen(name".out", "w", stdout); }
      |                                                                                    ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
skyscraper.cpp:22:5: note: in expansion of macro 'file'
   22 |     file("A") else file("task");
      |     ^~~~
skyscraper.cpp:2:58: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
    2 | #define file(name)  if (fopen(name".inp", "r")) { freopen(name".inp", "r", stdin); freopen(name".out", "w", stdout); }
      |                                                   ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
skyscraper.cpp:22:20: note: in expansion of macro 'file'
   22 |     file("A") else file("task");
      |                    ^~~~
skyscraper.cpp:2:91: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
    2 | #define file(name)  if (fopen(name".inp", "r")) { freopen(name".inp", "r", stdin); freopen(name".out", "w", stdout); }
      |                                                                                    ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
skyscraper.cpp:22:20: note: in expansion of macro 'file'
   22 |     file("A") else file("task");
      |                    ^~~~

• Subtask 1: 0 / 5
• Subtask 2: 15 / 15
• Subtask 3: 0 / 80