【BZOJ4698】[SDOI2008]Sandy的卡片

flag倒了。

bzoj

题解

#include <iostream>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <cmath>
#include <algorithm>
using namespace std;
inline int gi() {
register int data = 0, w = 1;
register char ch = 0;
while (!isdigit(ch) && ch != '-') ch = getchar();
if (ch == '-') w = -1, ch = getchar();
while (isdigit(ch)) data = 10 * data + ch - '0', ch = getchar();
return w * data;
}
const int MAX_N = 2e6 + 5;
int N, T, a[MAX_N], b[MAX_N], vis[MAX_N];
int sa[MAX_N], rnk[MAX_N], lcp[MAX_N];
void GetSA() {
#define cmp(i, j, k) (y[i] == y[j] && y[i + k] == y[j + k])
static int x[MAX_N], y[MAX_N], bln[MAX_N];
int M = 1e6;
for (int i = 1; i <= N; i++) bln[x[i] = a[i]]++;
for (int i = 1; i <= M; i++) bln[i] += bln[i - 1];
for (int i = N; i >= 1; i--) sa[bln[x[i]]--] = i;
for (int k = 1; k <= N; k <<= 1) {
int p = 0;
for (int i = 0; i <= M; i++) y[i] = 0;
for (int i = N - k + 1; i <= N; i++) y[++p] = i;
for (int i = 1; i <= N; i++) if (sa[i] > k) y[++p] = sa[i] - k;
for (int i = 0; i <= M; i++) bln[i] = 0;
for (int i = 1; i <= N; i++) bln[x[y[i]]]++;
for (int i = 1; i <= M; i++) bln[i] += bln[i - 1];
for (int i = N; i >= 1; i--) sa[bln[x[y[i]]]--] = y[i];
swap(x, y); x[sa[1]] = p = 1;
for (int i = 2; i <= N; i++) x[sa[i]] = cmp(sa[i], sa[i - 1], k) ? p : ++p;
if (p >= N) break;
M = p;
}
}
void GetLcp() {
for (int i = 1; i <= N; i++) rnk[sa[i]] = i;
for (int i = 1, j = 0; i <= N; i++) {
if (j) --j;
while (a[i + j] == a[sa[rnk[i] - 1] + j]) ++j;
lcp[rnk[i]] = j;
}
}
int col[MAX_N], tot;
bool check(int v) {
++tot; int cnt = 0;
for (int i = 1; i <= N; i++) {
if (lcp[i] < v) ++tot, cnt = 0;
if (col[vis[sa[i]]] != tot) col[vis[sa[i]]] = tot, ++cnt;
if (cnt == T) return 1;
}
return 0;
}
const int dlt = 5e4;
int main () {
T = gi();
for (int i = 1; i <= T; i++) {
int m = gi();
for (int j = 1; j <= m; j++) b[j] = gi();
for (int j = 1; j <= m; j++) b[j] = b[j + 1] - b[j] + dlt;
for (int j = 1; j < m; j++) a[++N] = b[j], vis[N] = i;
a[++N] = i + 5e5;
}
GetSA(); GetLcp();
int l = 0, r = N, ans = 0;
while (l <= r) {
int mid = (l + r) >> 1;
if (check(mid)) l = mid + 1, ans = mid;
else r = mid - 1;
}
printf("%d\n", ans + 1);
return 0;
}

posted @ 2019-01-22 19:21  heyujun  阅读(244)  评论(2编辑  收藏  举报