Suffix array Hunzi brush title record

Luo Gu P3809 [template] suffix sorting

• First to one of the most water template title o (* ≧ ▽ ≦) tsu ┏━┓
• SA [Nmax]   SA [i] ranking as the number of subscript i is the number
• the X-[Nmax]     the X-[i] value, value, each cycle should be based on the updated rankings again
• Y [Nmax of]     Y [i] as an intermediate array using twice, first SA [i] is updated according to the position of the second keyword ranking number i of the first key, the second update X [i] (since Comparative used when the original value x [i], it first with y [i] to update, the last y [i] is assigned to x [i])
• qsort () function known per second from the keyword ranking (y [i]) and a first key value (x [i]) find the rank number, using a radix sort result in sa [i] inside
• After each cycle state: x [i], sa [i] has been determined
• The outermost loop l: current corresponding to sa [i] of the l, after this cycle sa [i] refer to the length becomes 2l
• So l <n (or <= n / 2) 
• With great difficulty writing bad either suffix array. . . Code is wrong some easy points
• Code:
  

  . 1 #include <bits / STDC ++ H.>
   2  #define Nmax of 1000010
   . 3  
  . 4  the using  namespace STD;
   . 5  int C [Nmax of], RK [Nmax of], SA [Nmax of], X [Nmax of], Y [Nmax of];
   . 6  / / Y [i] a second keyword ranking number i of the position of the first keyword 
  . 7  
  . 8  char S [Nmax of];
   . 9  int n-, K, m = 200 is ;
   10  
  . 11  void qsort () {
   12 is      for ( int i = . 1 ; I <= m; I ++) C [I] = 0 ;
   13 is      for ( int I = . 1; i<=n; i++) c[ x[i] ]++;
  14     for (int i=1; i<=m; i++) c[i]+=c[i-1];
  15     for (int i=n; i>=1; i--) sa[ c[ x[y[i]] ]-- ]=y[i];
  16 }
  17 
  18 int main(){
  19     scanf("%s",s+1);
  20     n=strlen(s+1);
  21     for (int i=1; i<=n; i++) x[i]=s[i];
  22     for (int I = . 1 ; I <= n-; I ++) Y [I] = I;
   23 is      qsort ();
   24      for ( int L = . 1 ; L <n-; L << = . 1 ) { 
   25          int T = 0 ;
   26 is          for ( int I = n-L-+ . 1 ; I <= n-; I ++) Y [T ++] = I; 
   27          // some figures are not the first key, the second key is not sa some numbers [i ] can cover the range of 
  28          for ( int I = . 1 ; I <= n-; I ++) IF (SA [I]> L) Y [T ++] = SA [I] -l;   // if there is a first keywords 
  29          qsort ();
   30         m = . 1 ;
   31 is          Y [SA [ . 1 ]] = m;
   32          for ( int I = 2 ; I <= n-; I ++ ) {
   33 is              // fallibility Here, sa [i] refer to the lengths 2l, but x refers to the length of only l, so also the second keyword comparison 
  34 is              IF (x [SA [I]] == x [SA [I- . 1 ]]) IF (x [SA [I] + L] = X = [SA [I- . 1 ] + L]) {Y [SA [I]] = m; Continue ;}
   35              Y [SA [I]] ++ = m;
   36          }
   37 [          for ( int I = . 1 ; I <= n-; I ++) X [I] = Y [I];
   38 is     }
  39     for (int i=1; i<=n; i++) printf("%d ",sa[i]);
  40     return 0;
  41 }

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