Submission #127025

# Submission time Handle Problem Language Result Execution time Memory
127025 2019-07-08T19:59:03 Z eriksuenderhauf Sailing Race (CEOI12_race) C++11
75 / 100
3000 ms 7544 KB
//#pragma GCC optimize("O3")
#include <bits/stdc++.h>
#define enl printf("\n")
#define ni(n) scanf("%d", &(n))
#define pri(n) printf("%d\n", (n))
#define pii pair<int, int>
#define pll pair<long long, long long>
#define vii vector<pii>
#define vi vector<int>
#define pb push_back
#define mp make_pair
#define fi first
#define se second
using namespace std;
typedef long long ll;
const int MAXN = 5e2 + 2;
const int INF = 1e9 + 7;
int ans[MAXN], mx[MAXN][MAXN][2];
int dp[MAXN][MAXN][2], dp2[MAXN][MAXN][2];
int adj[MAXN][MAXN];
vi nex[MAXN];
int n;

bool between(int l, int r, int x) {
    if (l > r)
        return l < x || x < r;
    return l < x && x < r;
}

int solve(int l, int r, int k) {// path ends at r, interval at l
    if (~dp[l][r][k]) return dp[l][r][k];
    int &ret = dp[l][r][k];
    ret = 0;
    if (k) { // ccw
        //for (int i = (r%n) + 1; i != l; i = (i%n) + 1)
            //if (adj[r][i])
        for (int i: nex[r])
            if (between(r, l, i))
                ret = max(ret, max(solve(r, i, 0),  solve(l, i, 1)) + 1);
    } else { // cw
        //for (int i = (l%n) + 1; i != r; i = (i%n) + 1)
            //if (adj[r][i])
        for (int i: nex[r])
            if (between(l, r, i))
                ret = max(ret, max(solve(r, i, 1), solve(l, i, 0)) + 1);
    }
    return ret;
}

int f2(int l, int r, int k) {
    if (l == r)
        return 0;
    if (~dp2[l][r][k])
        return dp2[l][r][k];
    int ret = adj[l][r] ? 0 : -INF;
    if (k) {
        //for (int i = r%n+1; i != l; i = (i%n) + 1)
            //if (adj[l][i])
        for (int i: nex[l])
            if (between(r, l, i))
                ret = max(ret, f2(i, r, 1));
    } else {
        //for (int i = l%n+1; i != r; i = (i%n) + 1)
            //if (adj[l][i])
        for (int i: nex[l])
            if (between(l, r, i))
                ret = max(ret, f2(i, r, 0));
    }
    return dp2[l][r][k] = ret + 1;
}

int main() {
    memset(dp, -1, sizeof dp);
    memset(dp2, -1, sizeof dp2);
    int k;
    scanf("%d %d", &n, &k);
    for (int i = 1; i <= n; i++) {
        while (1) {
            int x; ni(x);
            if (x == 0)
                break;
            adj[i][x] = 1;
            nex[i].pb(x);
        }
    }
    for (int i = 1; i <= n; i++)
        for (int j: nex[i])
            ans[i] = max(ans[i], max(solve(i, j, 0), solve(i, j, 1)) + 1);
    if (k == 1) for (int i = 1; i <= n; i++) {
        for (int x = (i%n) + 1; x != i; x = (x%n) + 1)
            for (int y = (x+1)%n + 1; y != i; y = (y%n) + 1)
                if (adj[i][(y+n-2)%n + 1])
                    mx[x][y][0] = max(solve(x, (y+n-2)%n + 1, 0) + 1, mx[x][(y+n-2)%n + 1][0]);
                else
                    mx[x][y][0] = max(0, mx[x][(y+n-2)%n + 1][0]);
        for (int x = (i+n-2)%n+1; x != i; x = (x-2+n)%n+1)
            for (int y = (x+2*n-3)%n+1; y != i; y = (y-2+n)%n+1)
                if (adj[i][y%n+1])
                    mx[y][x][1] = max(solve(x, y%n+1, 1) + 1, mx[y%n+1][x][1]);
                else
                    mx[y][x][1] = max(0, mx[y%n+1][x][1]);

        for (int l = i%n+1; l != (i+2*n-3)%n+1; l = (l%n) + 1)
            for (int j = (l+1)%n+1; j != i; j = (j%n) + 1) {
                if (adj[l][j])
                    ans[l] = max(ans[l], max(f2(j, i, 0) + mx[l][j][0], f2(j, i, 0) + mx[l][j][1]) + 1);
                if (adj[j][l])
                    ans[j] = max(ans[j], max(f2(l, i, 1) + mx[l][j][0], f2(l, i, 1) + mx[l][j][1]) + 1);
            }
    }
    int ind = 0;
    for (int i = 1; i <= n; i++)
        if (ans[ind] < ans[i])
            ind = i;
    printf("%d\n%d\n", ans[ind], ind);
    return 0;
}

Compilation message

race.cpp: In function 'int main()':
race.cpp:76:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d %d", &n, &k);
     ~~~~~^~~~~~~~~~~~~~~~~
race.cpp:4:20: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
 #define ni(n) scanf("%d", &(n))
               ~~~~~^~~~~~~~~~~~
race.cpp:79:20: note: in expansion of macro 'ni'
             int x; ni(x);
                    ^~
# Verdict Execution time Memory Grader output
1 Correct 5 ms 4344 KB Output is correct
2 Correct 6 ms 4472 KB Output is correct
3 Correct 6 ms 4472 KB Output is correct
4 Correct 8 ms 4600 KB Output is correct
5 Correct 6 ms 4344 KB Output is correct
6 Correct 12 ms 4600 KB Output is correct
7 Correct 8 ms 4472 KB Output is correct
8 Correct 19 ms 4728 KB Output is correct
9 Correct 9 ms 4472 KB Output is correct
10 Correct 16 ms 4600 KB Output is correct
11 Correct 10 ms 4472 KB Output is correct
12 Correct 217 ms 5724 KB Output is correct
13 Correct 629 ms 6264 KB Output is correct
14 Correct 56 ms 5112 KB Output is correct
15 Execution timed out 3039 ms 7388 KB Time limit exceeded
16 Execution timed out 3042 ms 7416 KB Time limit exceeded
17 Execution timed out 3050 ms 7508 KB Time limit exceeded
18 Correct 79 ms 5372 KB Output is correct
19 Execution timed out 3045 ms 7544 KB Time limit exceeded
20 Execution timed out 3048 ms 7516 KB Time limit exceeded