C - Distinct Substrings （模板）

標籤：swa   while   space   scan   sub   char   color   res   pre   

https://vjudge.net/problem/SPOJ-DISUBSTR

有兩種方式來求去除重讀的子串

 1 #include <bits/stdc++.h> 2 using namespace std; 3 typedef long long ll; 4 const int maxn = 50005; 5  6 int t1[maxn],t2[maxn],c[maxn]; 7 bool cmp(int *r,int a,int b,int l)  { 8     return r[a]==r[b] &&r[l+a] == r[l+b]; 9 }10 11 void get_sa(int str[],int sa[],int Rank[],int height[],int n,int m)12 {13     n++;14     int p,*x=t1,*y=t2;15     for(int i = 0; i < m; i++) c[i] = 0;16     for(int i = 0; i < n; i++) c[x[i] = str[i]]++;17     for(int i = 1; i < m; i++) c[i] += c[i-1];18     for(int i = n-1; i>=0; i--) sa[--c[x[i]]] = i;19     for(int j = 1; j <= n; j <<= 1)  {20         p = 0;21         for(int i = n-j; i < n; i++) y[p++] = i;22         for(int i = 0; i < n; i++) if(sa[i] >= j) y[p++] = sa[i]-j;23         for(int i = 0; i < m; i++) c[i] = 0;24         for(int i = 0; i < n; i++) c[x[y[i]]]++ ;25         for(int i = 1; i < m; i++) c[i] += c[i-1];26         for(int i = n-1; i >= 0; i--)  sa[--c[x[y[i]]]] = y[i];27         swap(x,y);28         p = 1;29         x[sa[0]] = 0;30         for(int i = 1; i < n; i++)31             x[sa[i]] = cmp(y,sa[i-1],sa[i],j)? p-1:p++;32         if(p >= n) break;33         m = p;34     }35     int k = 0;36     n--;37     for(int i = 0; i <= n; i++)38         Rank[sa[i]] = i;39     for(int i = 0; i < n; i++)  {40         if(k) k--;41         int j = sa[Rank[i]-1];42         while(str[i+k] == str[j+k]) k++;43         height[Rank[i]] = k;44     }45 }46 47 int Rank[maxn],height[maxn];48 int sa[maxn];49 char str[maxn];50 int a[maxn];51 int n;52 53 int main()54 {55     int T;56     scanf("%d",&T);57     while(T--)58     {59         int tot = 0;60         scanf("%s",str);61         int len = strlen(str);62         for(int i = 0;i < len; i++)63             a[i] = str[i];64         a[len] = 0;65         get_sa(a,sa,Rank,height,len,200);66         long long res = 0;67         long long ans = (len+1)*len/2;68         for(int i=1;i<=len;i++){69             res+=len-sa[i]-height[i];70             ans-=height[i];71         }72         //printf("%lld\n",res);73         printf("%lld\n", ans);74     }75     return 0;76 }

 

C - Distinct Substrings （模板）