哈希一超过 65536 就爆炸。
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  • 发布时间2023/8/3 21:13
  • 上次更新2023/11/3 06:04:03
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哈希一超过 65536 就爆炸。
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fjy666楼主2023/8/3 21:13
//If zxx read this, send a QQ message to me >_<
#include <bits/stdc++.h>
using namespace std;
#define _rep(i_,a_,b_) for(int i_ = (a_); i_ <= (b_); ++i_)
#define mid ((L+R) >> 1)
#define multiCase() int testCnt = in(); _rep(curCase,1,testCnt)
#ifdef ONLINE_JUDGE
#define debug(...) 0
#else
#define debug(...) fprintf(stderr, __VA_ARGS__), fflush(stderr)
#endif
using ll = long long;
using pii = pair<int,int>;

int in(void) { int x; scanf("%d", &x); return x; } ll inl(void) { ll x; scanf("%lld", &x); return x; }
void out(int x) { printf("%d ", x); } void outln(int x) { printf("%d\n", x); }
void out(ll x) { printf("%lld ", x); } void outln(ll x) { printf("%lld\n", x); }
template<typename T> void chkmax(T &a, const T &b) { a = max(a, b); } 
template<typename T> void chkmin(T &a, const T &b) { a = min(a, b); } 
const int kN = 200500, p = 5004227, base = 131;
char s[kN]; 
struct SAM {
	int ch[kN][26], len[kN], link[kN], nc, last;
	void init(void) { link[0] = -1; }
	int clone(int x) {
		++nc;
		memcpy(ch[nc], ch[x], sizeof(ch[nc]));
		len[nc] = len[x];
		link[nc] = link[x];
		return nc;
	}
	void extend(char c) {
		c -= 'a';
		int cur = ++nc; len[cur] = len[last] + 1;
		while(~last && !ch[last][c]) ch[last][c] = cur, last = link[last];
		if(last == -1) link[cur] = 0;
		else {
			int p = ch[last][c];
			if(len[p] == len[last] + 1) link[cur] = p;
			else {
				int q = clone(p); len[q] = len[last] + 1;
				while(~last && ch[last][c] == p) ch[last][c] = q, last = link[last];
				link[p] = link[cur] = q;
			}
		}
		last = cur;
	}
} a, r;
/*set<int> S[kN];int hsh[kN], lcs[kN]; */ int cnt[kN], ord[kN], pw[kN];
// auto qwq = [](int x) -> int { return 1ll * x * x % p * x % p * x % p; };
int rt[p], ch[kN][2], val[kN], key[kN], nc; unsigned int rp[kN];
ll sum[kN];
mt19937 engine(114514);
void pushup(int x) { sum[x] = sum[ch[x][0]] + sum[ch[x][1]] + val[x]; }
void rotate(int &x, int d) {
	int y = ch[x][d]; ch[x][d] = ch[y][d ^ 1]; ch[y][d ^ 1] = x;
	pushup(x); pushup(x = y);
}
void insert(int &x, int v, int len) {
	if(!x) { x = ++nc, key[x] = v, val[x] = sum[x] = len, rp[x] = engine(); return; }
	int d = v >= key[x];
	insert(ch[x][d], v, len); pushup(x);
	if(rp[ch[x][d]] > rp[x]) rotate(x, d);
}
int query(int x, int v) {
	if(!x) return 0;
	if(v < key[x]) return sum[ch[x][1]] + val[x] + query(ch[x][0], v);
	else return query(ch[x][1], v);
}
int prefix[kN];
vector<int> g[kN];
// int fa[20][kN], dep[kN], lg[kN];
int st[20][kN], lg[kN], dfn[kN], dfs_clock;
void dfs(int u, int f) {
	dfn[u] = ++dfs_clock; st[0][dfs_clock] = f;
	// fa[0][u] = f, dep[u] = dep[f] + 1;
	// _rep(i,1,19) fa[i][u] = fa[i - 1][fa[i - 1][u]];
	for(auto &v : g[u]) dfs(v, u);
}
int dfnMin(int u, int v) { return dfn[u] < dfn[v] ? u : v; }
int lca(int u, int v) {
	assert(0 <= u && u <= r.nc && 0 <= v && v <= r.nc);
	if(u == v) return u;
	if(dfn[u] > dfn[v]) swap(u, v);
	int k = lg[dfn[v] - dfn[u]];
	return dfnMin(st[k][dfn[u] + 1], st[k][dfn[v] - (1 << k) + 1]);
}
// int lca(int u, int v) {
	// while(dep[u] != dep[v]) {
	// 	if(dep[u] < dep[v]) swap(u, v);
	// 	u = fa[lg[dep[u] - dep[v]]][u];
	// }
	// if(u == v) return u;
	// for(int i = 19; ~i; --i) if(fa[i][u] != fa[i][v]) u = fa[i][u], v = fa[i][v];
	// return fa[0][u];
// }
namespace merge {
	int ch[kN * 30][2], hsh[kN * 30], lft[kN * 30], rgt[kN * 30], siz[kN * 30], lcs[kN * 30], nc;
	void pushup(int x) {
		// debug("call pushup\n");
		if(!ch[x][0] || !ch[x][1]) {
			assert(ch[x][0] || ch[x][1]);
			// debug("pushup with one son missing.\n");
			hsh[x] = hsh[ch[x][0] + ch[x][1]];
			lft[x] = lft[ch[x][0] + ch[x][1]];
			rgt[x] = rgt[ch[x][0] + ch[x][1]];
			siz[x] = siz[ch[x][0] + ch[x][1]];
			lcs[x] = lcs[ch[x][0] + ch[x][1]];
			return;
		} 
		siz[x] = siz[ch[x][0]] + siz[ch[x][1]];
		hsh[x] = (1ll * hsh[ch[x][0]] + 1ll * pw[siz[ch[x][0]]] * (lft[ch[x][1]] - rgt[ch[x][0]]) % p +
			1ll * pw[siz[ch[x][0]] + 1] * hsh[ch[x][1]] % p) % p;
		lft[x] = lft[ch[x][0]];
		rgt[x] = rgt[ch[x][1]];	
		lcs[x] = lca(lcs[ch[x][0]], lcs[ch[x][1]]);
	}
	void insert(int &x, int L, int R, int p) {
		// debug("Insert %d, [%d, %d], p = %d\n", x, L, R, p);
		if(!x) x = ++nc, ch[x][0] = ch[x][1] = lft[x] = rgt[x] = siz[x] = hsh[x] = lcs[x] = 0;
		if(L == R) {
			assert(p == L);
			hsh[x] = 0;
			lft[x] = rgt[x] = L;
			siz[x] = 1;
			lcs[x] = prefix[L]; 
			return;
		}
		if(p <= mid) insert(ch[x][0], L, mid, p);
		else insert(ch[x][1], mid + 1, R, p);
		pushup(x);
	}
	int merge(int x, int y) {
		if(!x || !y) return x + y;
		ch[x][0] = merge(ch[x][0], ch[y][0]);
		ch[x][1] = merge(ch[x][1], ch[y][1]);
		pushup(x);
		return x;
	}
	int getfirst(int x, int L, int R) {
		assert(x);
		if(L == R) return L;
		return siz[ch[x][0]] ? getfirst(ch[x][0], L, mid) : getfirst(ch[x][1], mid + 1, R);
	}
}
int rt_t[kN];
void outln(__int128 x) {
	if(x > 9) outln(x / 10);
	putchar(x % 10 + '0');
}
int main() {
	// freopen("data.txt", "r", stdin);
	_rep(i,2,kN - 1) lg[i] = lg[i >> 1] + 1;
	pw[0] = 1; _rep(i,1,kN - 1) pw[i] = 1ll * pw[i - 1] * base % p, assert(pw[i] != 1);
	// for(int i = kN - 1; ~i; --i) debug("pw[%d] = %d\n", i, pw[i]);
	a.init(), r.init();
	scanf("%s", s + 1);
	int n = strlen(s + 1);
	for(int i = n; i; --i) {
		r.extend(s[i]), prefix[i] = r.last;
		// S[r.last].insert(i), 
		merge::insert(rt_t[r.last], 1, n, i);
	}
	_rep(i,1,r.nc) ++cnt[r.len[i]];
	_rep(i,1,n) cnt[i] += cnt[i - 1];
	_rep(i,1,r.nc) ord[cnt[r.len[i]]--] = i;
	for(int i = r.nc; i; --i) {
		int u = ord[i], fu = r.link[u];
		// debug("Get u = %d\n", u);
		// debug("Get u = %d, hsh[u] = %d\n", u, merge::hsh[rt_t[u]]);
		// debug("Startpos(u) = [");
		// for(auto &x : S[u]) debug("%d ", x);
		// debug("]\n");
		// hshcnt[hsh[u]] += r.len[u] - r.len[fu];
		// int smallest = *S[u].begin();
		int hshv = merge::hsh[rt_t[u]];
		// debug("hshv = %d, lft = %d, rgt = %d\n", hshv, merge::lft[rt_t[u]], merge::rgt[rt_t[u]]);
		int smallest = merge::getfirst(rt_t[u], 1, n);
		insert(rt[hshv], smallest, r.len[u] - r.len[fu]);
		rt_t[fu] = merge::merge(rt_t[fu], rt_t[u]);
		// set<int> &A = S[u], &B = S[fu];
		// if(A.size() > B.size()) swap(A, B), swap(hsh[u], hsh[fu]);
		// for(auto &x : A) {
		// 	auto it = B.lower_bound(x);
		// 	if(it == B.begin()) hsh[fu] = (hsh[fu] + qwq(*B.begin() - x)) % p, B.insert(x); 
		// 	else if(it == B.end()) hsh[fu] = (hsh[fu] + qwq(x - *--B.end())) % p, B.insert(x);
		// 	else {
		// 		hsh[fu] -= qwq(*it - *prev(it));
		// 		hsh[fu] += qwq(x - *prev(it)) + qwq(*it - x);
		// 		hsh[fu] = (hsh[fu] % p + p) % p;
		// 		B.insert(x);
		// 	}
		// }
		// A.clear();
	}
	assert(merge::nc < kN * 30);
	assert(nc < kN);
	debug("SAM nc = %d, BST nc = %d, SGT nc = %d\n", r.nc, nc, merge::nc);
	merge::nc = 0;
	// memset(merge::ch, 0, sizeof(merge::ch));
	// memset(merge::hsh, 0, sizeof(merge::hsh));
	// memset(merge::lft, 0, sizeof(merge::lft));
	// memset(merge::rgt, 0, sizeof(merge::rgt));
	// memset(merge::siz, 0, sizeof(merge::siz));
	// memset(merge::lcs, 0, sizeof(merge::lcs));
	memset(rt_t, 0, sizeof(rt_t));
	memset(cnt, 0, sizeof(cnt));
	// memset(ord, 0, sizeof(ord));
	// _rep(i,1,r.nc) S[i].clear(); memset(hsh, 0, sizeof(hsh));
	// memset(cnt, 0, sizeof(cnt)); memset(ord, 0, sizeof(ord));
	_rep(i,1,n) a.extend(s[i]), /*S[a.last].insert(i),lcs[a.last] = prefix[i],*/ merge::insert(rt_t[a.last], 1, n, i);  //, prefix[i] = a.last;
	_rep(i,1,r.nc) g[r.link[i]].push_back(i);
	dfs(0, 0);
	assert(dfs_clock == r.nc + 1);
	_rep(i,1,19) _rep(j,1,r.nc + 1 - (1 << i) + 1) st[i][j] = dfnMin(st[i - 1][j], st[i - 1][j + (1 << (i - 1))]);
	_rep(i,1,a.nc) ++cnt[a.len[i]];
	_rep(i,1,n) cnt[i] += cnt[i - 1];
	_rep(i,1,a.nc) ord[cnt[a.len[i]]--] = i;
	__int128 res = 0;
	for(int i = a.nc; i; --i) {
		int u = ord[i], fu = a.link[u];
		// debug("Get u = %d\n", u);
		// debug("Get u = %d, hsh[u] = %d\n", u, merge::hsh[rt_t[u]]);
		// debug("Endpos(u) = [");
		// for(auto &x : S[u]) debug("%d ", x);
		// debug("]\n");
		int hshv = merge::hsh[rt_t[u]];
		// debug("hshv = %d, lft = %d, rgt = %d\n", hshv, merge::lft[rt_t[u]], merge::rgt[rt_t[u]]);
		// insert(rt[hshv], smallest, r.len[u] - r.len[fu]);
		// int smallest = *S[u].begin();
		// int L = smallest, R = n, bs = -1;
		// while(L <= R) {
		// 	int x = prefix[mid];
		// 	for(int i = 19; ~i; --i) if(a.len[fa[i][x]] >= mid - smallest + 1) x = fa[i][x];
		// 	if(lca(x, u) == x) bs = mid, L = mid + 1;
		// 	else R = mid - 1;
		// }
		// chkmax(mx[hsh[u]], fst[u] = smallest);
		int smallest = merge::getfirst(rt_t[u], 1, n);
		int bs = r.len[merge::lcs[rt_t[u]]];
		assert(bs >= 1);
		// debug("delta res = %d * %d\n", (a.len[u] - a.len[fu]), query(rt[hsh[u] % kN], smallest));
		// debug("bs = %d, df = %d\n", bs, query(rt[hsh[u]], smallest + bs));
		res += (__int128_t) (a.len[u] - a.len[fu]) * (query(rt[hshv], smallest) - query(rt[hshv], smallest + bs));
		// debug("Delta res = %d * %d\n", a.len[u] - a.len[fu], query(rt[hshv], smallest) - query(rt[hshv], smallest + bs));
		rt_t[fu] = merge::merge(rt_t[fu], rt_t[u]);
		// set<int> &A = S[u], &B = S[fu];
		// if(A.size() > B.size()) swap(A, B), swap(hsh[u], hsh[fu]), swap(lcs[u], lcs[fu]);
		// for(auto &x : A) {
		// 	auto it = B.lower_bound(x);
		// 	if(it == B.begin()) hsh[fu] = (hsh[fu] + qwq(*B.begin() - x)) % p, B.insert(x); 
		// 	else if(it == B.end()) hsh[fu] = (hsh[fu] + qwq(x - *--B.end())) % p, B.insert(x);
		// 	else {
		// 		hsh[fu] -= qwq(*it - *prev(it));
		// 		hsh[fu] += qwq(x - *prev(it)) + qwq(*it - x);
		// 		hsh[fu] = (hsh[fu] % p + p) % p;
		// 		B.insert(x);
		// 	}
		// 	lcs[fu] = lca(lcs[fu], prefix[x]);
		// }
		// A.clear();
	}
	// _rep(i,1,a.nc) chkmax(gst[ord[i]] = mx[hsh[ord[i]]], gst[a.link[ord[i]]]);
	// _rep(i,1,a.nc) gst[ord[i]] = mx[hsh[ord[i]]];
	// _rep(i,1,a.nc) res += 1ll * (a.len[i] - a.len[a.link[i]]) * (query(rt[hsh[i]], fst[i]) - query(rt[hsh[i]], gst[i] + 1));
	outln(res);
	assert(merge::nc < kN * 30);
	// assert(nc < kN);
	return 0;
}

/* 
a list of keywords
clear empty push_back pop_back push pop top front back
emplace_back emplace push_front pop_front insert erase
find count set reset bitset map vector string multiset
first second iterator prev next deque multimap reverse
sort begin end list modify query init check calc prime
putchar getchar puts scanf printf max min swap replace
make_pair make_tuple numeric_limits auto function null
*/

救救孩子。调了一天了。或者给几个好用的hash底数&模数也行

2023/8/3 21:13
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