oj.uz

답안 #202615

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
202615 2020-02-17T10:18:09 Z rdd6584 Lampice (COCI19_lampice) C++14
42 / 110
 1099 ms 11816 KB 
#include <bits/stdc++.h>
#define sz(x) (int)(x).size()
#define all(x) (x).begin(), (x).end()
using namespace std;

typedef long long ll;
typedef unsigned long long llu;
typedef pair<int, int> pii;
typedef pair<int, pii> piii;
typedef pair<ll, ll> pll;
typedef pair<ll, int> pli;
typedef pair<int, ll> pil;
typedef pair<string, int> psi;
typedef pair<char, int> pci;
typedef pair<int, char> pic;
const long double PI = 3.141592653589793238462643383279502884197;

int n;
const int B = 128;
const ll pr[2] = { 1000000009, 1000000021 };
ll rhq[50002][2];

vector<int> v[50002];
int rotn[50002];
char visit[50002];
char s[50002];
int flag = 0;

int cent(int o, int pa, int cap) {
    for (int i : v[o])
        if (i != pa && !visit[i] && rotn[i] > cap)
            return cent(i, o, cap);
    return o;
}

int pre(int o, int pa) {
    int ret = 1;
    for (int i : v[o])
        if (i != pa && !visit[i])
            ret += pre(i, o);

    return rotn[o] = ret;
}

unordered_map<ll, int> um;
deque<char> dq;

void pcal(int o, int pa, int di, int h1, int h2) {
    h1 = (h1 + rhq[di][0] * s[o]) % pr[0];
    h2 = (h2 + rhq[di][1] * s[o]) % pr[1]; // 경로 길이 반환..

    int ha = h1 * rhq[n - di][0] % pr[0];  // 끝의 높이를 n에 맞춰줌
    int hb = h2 * rhq[n - di][1] % pr[1];
    um[ha * pr[1] + hb]++;

    for (int i : v[o])
        if (i != pa && !visit[i])
            pcal(i, o, di + 1, h1, h2);
}

void mcal(int o, int pa, int di, int h1, int h2) {
    h1 = (h1 + rhq[di][0] * s[o]) % pr[0];
    h2 = (h2 + rhq[di][1] * s[o]) % pr[1];

    int ha = h1 * rhq[n - di][0] % pr[0];
    int hb = h2 * rhq[n - di][1] % pr[1];
    um[ha * pr[1] + hb]--;

    for (int i : v[o])
        if (i != pa && !visit[i])
            mcal(i, o, di + 1, h1, h2);
}

void cal(int o, int pa, int di, int dd, int h1, int h2, int r1, int r2, int s1, int s2) {
    h1 = (h1 + rhq[di][0] * s[o]) % pr[0];
    h2 = (h2 + rhq[di][1] * s[o]) % pr[1];
    dq.push_back(s[o]);

    int ha, hb, sa, sb;
    vector<char> rev;
    while (dd <= di) {
        sa = s1 * rhq[n - (dd - 1)][0] % pr[0];
        sb = s2 * rhq[n - (dd - 1)][1] % pr[1];
        if (r1 == sa && r2 == sb) flag = max(flag, (di - dd) * 2 + dd);

        ha = (h1 - s1 + pr[0]) % pr[0];
        hb = (h2 - s2 + pr[1]) % pr[1];

        ha = ha * rhq[n - di][0] % pr[0];
        hb = hb * rhq[n - di][1] % pr[1];
        auto t = um.find(ha * pr[1] + hb);

        if (dd == 0 || t == um.end() || t->second <= 0) {
            char w = dq.front();
            dq.pop_front();
            rev.push_back(w);

            r1 = (r1 + rhq[n - dd][0] * w) % pr[0];
            r2 = (r2 + rhq[n - dd][1] * w) % pr[1];

            s1 = (s1 + rhq[dd][0] * w) % pr[0];
            s2 = (s2 + rhq[dd][1] * w) % pr[1];

            dd++;
        }
        else break;
    }

    sa = s1 * rhq[n - (dd - 1)][0] % pr[0];
    sb = s2 * rhq[n - (dd - 1)][1] % pr[1];
    if (r1 == sa && r2 == sb) flag = max(flag, (di - dd + 1) * 2 + dd);

    for (int i : v[o])
        if (i != pa && !visit[i]) {
            if (o == pa) mcal(i, o, 1, 0, 0);
            cal(i, o, di + 1, dd, h1, h2, r1, r2, s1, s2);
            if (o == pa) pcal(i, o, 1, 0, 0);
        }

    while (!rev.empty()) {
        dq.push_front(rev.back());
        rev.pop_back();
    }

    dq.pop_back();
}

void go(int o) {
    pre(o, o);
    int t = cent(o, o, rotn[o] / 2);
    visit[t]++;

    for (int i : v[t])
        if (!visit[i])
            pcal(i, t, 1, 0, 0);

    cal(t, t, 0, 0, 0, 0, 0, 0, 0, 0);
    dq.clear();
    um.clear();

    for (int i : v[t])
        if (!visit[i])
            go(i);

    visit[t]--;
}

int main() {
    scanf("%d", &n);
    scanf("%s", s);

    rhq[0][0] = rhq[0][1] = 1;
    for (int i = 1; i <= n; i++)
        for (int j = 0; j < 2; j++)
            rhq[i][j] = rhq[i - 1][j] * B % pr[j];

    for (int i = 0; i < n - 1; i++) {
        int a, b;
        scanf("%d %d", &a, &b);
        a--; b--;
        v[a].push_back(b);
        v[b].push_back(a);
    }

    /*
    int l = 0, r = (n - 1) / 2, mid;
    int ans = 0;
    while (l <= r) {
        mid = (l + r) / 2;
        flag = 0, len = mid * 2 + 1;

        go(0);
        if (flag) l = mid + 1;
        else r = mid - 1;
    }
    ans = max(ans, l * 2 + 1);

    l = 0, r = n / 2;
    while (l <= r) {
        mid = (l + r) / 2;
        flag = 0, len = mid * 2;

        go(0);
        if (flag) l = mid + 1;
        else r = mid - 1;
    }
    ans = max(ans, l * 2);
    printf("%d", ans);
    */

    go(0);
    printf("%d", flag);
}

Compilation message

lampice.cpp: In function 'int main()':
lampice.cpp:149:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d", &n);
     ~~~~~^~~~~~~~~~
lampice.cpp:150:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%s", s);
     ~~~~~^~~~~~~~~
lampice.cpp:159:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%d %d", &a, &b);
         ~~~~~^~~~~~~~~~~~~~~~~

Subtask #1
17.0 / 17.0

# 결과 실행 시간 메모리 Grader output
1 Correct 6 ms 1528 KB Output is correct
2 Correct 7 ms 1528 KB Output is correct
3 Correct 12 ms 1656 KB Output is correct
4 Correct 13 ms 1656 KB Output is correct
5 Correct 5 ms 1528 KB Output is correct
6 Correct 5 ms 1528 KB Output is correct
7 Correct 5 ms 1528 KB Output is correct

Subtask #2
25.0 / 25.0

# 결과 실행 시간 메모리 Grader output
1 Correct 805 ms 10664 KB Output is correct
2 Correct 829 ms 10544 KB Output is correct
3 Correct 828 ms 10408 KB Output is correct
4 Correct 894 ms 11180 KB Output is correct
5 Correct 949 ms 11816 KB Output is correct
6 Correct 530 ms 10488 KB Output is correct

Subtask #3
0 / 31.0

# 결과 실행 시간 메모리 Grader output
1 Correct 1099 ms 8104 KB Output is correct
2 Correct 975 ms 7592 KB Output is correct
3 Correct 960 ms 8104 KB Output is correct
4 Incorrect 623 ms 7416 KB Output isn't correct
5 Halted 0 ms 0 KB -

Subtask #4
0 / 37.0

# 결과 실행 시간 메모리 Grader output
1 Correct 6 ms 1528 KB Output is correct
2 Correct 7 ms 1528 KB Output is correct
3 Correct 12 ms 1656 KB Output is correct
4 Correct 13 ms 1656 KB Output is correct
5 Correct 5 ms 1528 KB Output is correct
6 Correct 5 ms 1528 KB Output is correct
7 Correct 5 ms 1528 KB Output is correct
8 Correct 805 ms 10664 KB Output is correct
9 Correct 829 ms 10544 KB Output is correct
10 Correct 828 ms 10408 KB Output is correct
11 Correct 894 ms 11180 KB Output is correct
12 Correct 949 ms 11816 KB Output is correct
13 Correct 530 ms 10488 KB Output is correct
14 Correct 1099 ms 8104 KB Output is correct
15 Correct 975 ms 7592 KB Output is correct
16 Correct 960 ms 8104 KB Output is correct
17 Incorrect 623 ms 7416 KB Output isn't correct
18 Halted 0 ms 0 KB -