hdu 3973 字串hash+線段樹
阿新 • • 發佈:2019-02-08
Problem Description
You are given some words {Wi}. Then our stupid AC will give you a very long string S. AC is stupid and always wants to know whether one substring from S exists in the given words {Wi} .
For example, S = "abcd", and the given words {Wi} = {"bc", "ad", "dd"}. Then Only S[2..3] = "bc" exists in the given words. (In this problem, the first element of S has the index "0".)
However, this is toooooooooooo easy for acmers ! The stupid and evil AC will now change some letters in S. So could you solve this problem now?
Input The first line is one integer T indicates the number of the test cases. (T <=20)
Then for every case, there is one integer n in the first line indicates the number of the given words(The size of the {Wi}) . Then n lines has one string which only has 'a'- 'z'. (1 <= n <= 10000, sigma|Wi| <= 2000000) .
Then one line has one string S, here |S| <= 100000.
Then one integer m, indicating the number of operations. (1 <= m <= 100000)
Then m lines , each line is the operation:
(1)Q L R , tell AC whether the S[L..R] exists in the given strings ;
(2)C X Y , chang S[X] to Y, here Y : 'a'-'z' .
Output First output “Case #idx:” in a single line, here idx is the case number count from 1.Then for each "Q" operation, output "Yes" if S[L..R] exists in the given strings, otherwise output "No".
Sample Input 1 2 ab ioc ipcad 6 Q 0 2 Q 3 4 C 1 o C 4 b Q 0 2 Q 3 4
Sample Output Case #1: No No Yes Yes
For example, S = "abcd", and the given words {Wi} = {"bc", "ad", "dd"}. Then Only S[2..3] = "bc" exists in the given words. (In this problem, the first element of S has the index "0".)
However, this is toooooooooooo easy for acmers ! The stupid and evil AC will now change some letters in S. So could you solve this problem now?
Input The first line is one integer T indicates the number of the test cases. (T <=20)
Then for every case, there is one integer n in the first line indicates the number of the given words(The size of the {Wi}) . Then n lines has one string which only has 'a'- 'z'. (1 <= n <= 10000, sigma|Wi| <= 2000000) .
Then one line has one string S, here |S| <= 100000.
Then one integer m, indicating the number of operations. (1 <= m <= 100000)
Then m lines , each line is the operation:
(1)Q L R , tell AC whether the S[L..R] exists in the given strings ;
(2)C X Y , chang S[X] to Y, here Y : 'a'-'z' .
Output First output “Case #idx:” in a single line, here idx is the case number count from 1.Then for each "Q" operation, output "Yes" if S[L..R] exists in the given strings, otherwise output "No".
Sample Input 1 2 ab ioc ipcad 6 Q 0 2 Q 3 4 C 1 o C 4 b Q 0 2 Q 3 4
Sample Output Case #1: No No Yes Yes
/** hdu 3973 線段樹單點更新區間求值+字串hash 題目大意:給定多個字串,然後給定一個大串,對該串進行單點更新和區間查詢,查詢的區間子串是不是在已知的字串中出現 解題思路:對字串進行hash處理採用線段樹來進行更新,用set存放字串的雜湊值。至於怎麼雜湊和大白書上的思路差不多隻是這裡是表示的字首 */ #include <stdio.h> #include <string.h> #include <iostream> #include <set> using namespace std; const int maxn=100010; const int seed=31; typedef unsigned long long LL; struct note { int l,r; LL hashes; }tree[maxn*4]; char str[2000100]; LL Hash[maxn]; int n; void init() { Hash[0]=1; for(int i=1;i<maxn;i++) { Hash[i]=Hash[i-1]*seed; } } LL get_hash() { int len=strlen(str); LL sum=0; for(int i=0;i<len;i++) sum=sum*seed+str[i]-'a'+1; return sum; } void build(int l,int r,int root) { tree[root].l=l; tree[root].r=r; if(l==r) { tree[root].hashes=str[l]-'a'+1; return; } int mid=(l+r)/2; build(l,mid,root<<1); build(mid+1,r,root<<1|1); tree[root].hashes=tree[root<<1].hashes*Hash[r-mid]+tree[root<<1|1].hashes; } void update(int l,int root) { if(tree[root].l==tree[root].r) { tree[root].hashes=str[l]-'a'+1; return; } int mid=(tree[root].l+tree[root].r)>>1; if(l<=mid) update(l,root<<1); else update(l,root<<1|1); tree[root].hashes=tree[root<<1].hashes*Hash[tree[root].r-mid]+tree[root<<1|1].hashes; } LL query(int l,int r,int root) { // printf("**\n"); if(tree[root].l==l&&tree[root].r==r) return tree[root].hashes; int mid=(tree[root].r+tree[root].l)>>1; if(r<=mid)return query(l,r,root<<1); else if(l>mid)return query(l,r,root<<1|1); return query(l,mid,root<<1)*Hash[r-mid]+query(mid+1,r,root<<1|1); } int main() { int T,tt=0; init(); scanf("%d",&T); while(T--) { printf("Case #%d:\n",++tt); scanf("%d",&n); set<LL>mp; for(int i=0;i<n;i++) { scanf("%s",str); mp.insert(get_hash()); } scanf("%s",str); int len=strlen(str); build(0,len-1,1); int q; scanf("%d",&q); for(int i=1;i<=q;i++) { char c[5]; scanf("%s",c); if(c[0]=='C') { int a; char b[10]; scanf("%d%s",&a,b); str[a]=b[0]; update(a,1); } else { int l,r; scanf("%d%d",&l,&r); if(mp.find(query(l,r,1))!=mp.end()) printf("Yes\n"); else printf("No\n"); } } } return 0; }