結果
問題 | No.1494 LCS on Tree |
ユーザー | 👑 ygussany |
提出日時 | 2021-04-30 23:02:23 |
言語 | C (gcc 13.3.0) |
結果 |
AC
|
実行時間 | 55 ms / 2,000 ms |
コード長 | 2,485 bytes |
コンパイル時間 | 570 ms |
コンパイル使用メモリ | 33,332 KB |
実行使用メモリ | 33,268 KB |
最終ジャッジ日時 | 2024-11-20 15:04:36 |
合計ジャッジ時間 | 2,810 ms |
ジャッジサーバーID (参考情報) |
judge5 / judge4 |
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ファイルパターン | 結果 |
---|---|
sample | AC * 3 |
other | AC * 47 |
ソースコード
#include <stdio.h>typedef struct List {struct List *next;int v;char c;} list;void chmin(int* a, int b){if (*a > b) *a = b;}void chmax(int* a, int b){if (*a < b) *a = b;}int main(){int i, N, s, u, w, x;char S[2001], c;list *adj[2001] = {}, e[4001], *p, *pp;scanf("%d", &N);scanf("%s", S);for (s = 0; S[s] != 0; s++);for (i = 0; i < N - 1; i++) {scanf("%d %d %c ", &u, &w, &c);e[i*2].v = w;e[i*2+1].v = u;e[i*2].c = c;e[i*2+1].c = c;e[i*2].next = adj[u];e[i*2+1].next = adj[w];adj[u] = &(e[i*2]);adj[w] = &(e[i*2+1]);}int par[2001] = {}, q[2001], head, tail;par[1] = 1;q[0] = 1;for (head = 0, tail = 1; head < tail; head++) {u = q[head];for (p = adj[u]; p != NULL; p = p->next) {w = p->v;if (par[w] == 0) {par[w] = u;q[tail++] = w;}}}int j, k, l, r, m, LCS[2][2001] = {}, LCS_pos[2][2001][2001], tmp[2001], ans = 0;for (u = 1; u <= N; u++) {for (i = 1, LCS_pos[0][u][0] = -1, LCS_pos[1][u][0] = s; i <= s; i++) {LCS_pos[0][u][i] = s;LCS_pos[1][u][i] = -1;}}for (head--; head >= 0; head--) {u = q[head];for (p = adj[u]; p != NULL; p = p->next) {w = p->v;c = p->c;if (w == par[u]) continue;for (i = s - 1; i >= 0; i--) {if (S[i] != c) continue;l = 0;r = LCS[0][w] + 1;while (l < r) {m = (l + r) / 2;if (LCS_pos[0][w][m] < i) l = m + 1;else r = m;}LCS_pos[0][w][l] = i;if (l == LCS[0][w] + 1) LCS[0][w]++;}for (i = 1; i <= LCS[0][w]; i++) chmin(&(LCS_pos[0][u][i]), LCS_pos[0][w][i]);chmax(&(LCS[0][u]), LCS[0][w]);for (i = 0; i < s; i++) {if (S[i] != c) continue;l = 0;r = LCS[1][w] + 1;while (l < r) {m = (l + r) / 2;if (LCS_pos[1][w][m] > i) l = m + 1;else r = m;}LCS_pos[1][w][l] = i;if (l == LCS[1][w] + 1) LCS[1][w]++;}for (i = 1; i <= LCS[1][w]; i++) chmax(&(LCS_pos[1][u][i]), LCS_pos[1][w][i]);chmax(&(LCS[1][u]), LCS[1][w]);}chmax(&ans, LCS[0][u]);chmax(&ans, LCS[1][u]);for (p = adj[u]; p != NULL; p = p->next) {w = p->v;if (w == par[u]) continue;for (pp = adj[u]; pp != NULL; pp = pp->next) {x = pp->v;if (x == par[u] || x == w) continue;for (i = 0, j = LCS[1][x]; i <= LCS[0][w]; i++) {for (; LCS_pos[1][x][j] <= LCS_pos[0][w][i]; j--);chmax(&ans, i + j);}}}}printf("%d\n", ans);fflush(stdout);return 0;}