Submission #127033

# Submission time Handle Problem Language Result Execution time Memory
127033 2019-07-08T20:14:13 Z eriksuenderhauf Sailing Race (CEOI12_race) C++11
80 / 100
3000 ms 7548 KB
#pragma GCC optimize("O3")
#include <bits/stdc++.h>
using namespace std;
const int MAXN = 5e2 + 1;
const int INF = 1e9 + 7;
int ans[MAXN], mx[MAXN][MAXN][2];
int dp[MAXN][MAXN][2], dp2[MAXN][MAXN][2];
bool adj[MAXN][MAXN];
int nex[MAXN][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;
    int lo = k ? r : l;
    int hi = l ^ r ^ lo;
    for (int i=1; i <= nex[r][0]; i++)
        if (between(lo, hi, nex[r][i]))
            ret = max(ret, max(solve(r, nex[r][i], k^1),  solve(l, nex[r][i], k)) + 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;
    int lo = k ? r : l;
    int hi = l ^ r ^ lo;
    for (int i=1; i <= nex[l][0]; i++)
        if (between(lo, hi, nex[l][i]))
            ret = max(ret, f2(nex[l][i], r, k));
    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++) {
        int x;
        while (1) {
            scanf("%d", &x);
            if (x == 0)
                break;
            adj[i][x] = 1;
            nex[i][++nex[i][0]] = x;
        }
    }
    for (int i = 1; i <= n; i++)
        for (int j=1; j <= nex[i][0]; j++)
            ans[i] = max(ans[i], max(solve(i, nex[i][j], 0), solve(i, nex[i][j], 1)) + 1);
    if (k == 1) for (int i = 1; i <= n; i++) {
        memset(mx, 0, sizeof mx);
        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);
            }
        if (ans[i] == n) break;
    }
    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:46:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d %d", &n, &k);
     ~~~~~^~~~~~~~~~~~~~~~~
race.cpp:50:18: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
             scanf("%d", &x);
             ~~~~~^~~~~~~~~~
# Verdict Execution time Memory Grader output
1 Correct 5 ms 4344 KB Output is correct
2 Correct 9 ms 6264 KB Output is correct
3 Correct 10 ms 6264 KB Output is correct
4 Correct 13 ms 6392 KB Output is correct
5 Correct 6 ms 4344 KB Output is correct
6 Correct 20 ms 6392 KB Output is correct
7 Correct 7 ms 4472 KB Output is correct
8 Correct 28 ms 6392 KB Output is correct
9 Correct 8 ms 4472 KB Output is correct
10 Correct 12 ms 4472 KB Output is correct
11 Correct 9 ms 4472 KB Output is correct
12 Correct 232 ms 6744 KB Output is correct
13 Correct 644 ms 6988 KB Output is correct
14 Correct 42 ms 5240 KB Output is correct
15 Execution timed out 3052 ms 7548 KB Time limit exceeded
16 Execution timed out 3037 ms 7544 KB Time limit exceeded
17 Correct 2977 ms 7480 KB Output is correct
18 Correct 54 ms 5496 KB Output is correct
19 Execution timed out 3033 ms 7416 KB Time limit exceeded
20 Execution timed out 3038 ms 7548 KB Time limit exceeded