Galil-Giancarlo example

First attempt
G C A T C G C A G A G A G T A T A C A G T A C G
  1 2   3  
G C A G A G A G  

Shift by: 3 (shift[2])

Second attempt
G C A T C G C A G A G A G T A T A C A G T A C G
  1 2  
  G C A G A G A G  

Shift by: 2 (shift[1])

Third attempt
G C A T C G C A G A G A G T A T A C A G T A C G
  8 1 2 7 3 6 4 5  
  G C A G A G A G  

Shift by: 7 (shift[8])

Fourth attempt
G C A T C G C A G A G A G T A T A C A G T A C G
  1  
  - G  

Shift by: 2

Fifth attempt
G C A T C G C A G A G A G T A T A C A G T A C G
  1  
  G C A G A G A G  

Shift by: 1 (shift[0])

Sixth attempt
G C A T C G C A G A G A G T A T A C A G T A C G
  1  
  G C A G A G A G  

Shift by: 1 (shift[0])

Seventh attempt
G C A T C G C A G A G A G T A T A C A G T A C G
  1 2   3  
  G C A G A G A G

Shift by: (shift[2])

The Galil-Giancarlo algorithm performs 19 character comparisons on the example.

Galil-Giancarlo algorithm