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KMP String Matching Algorithm What is the meaning of KMP? KMP  -  Knuth - Morris - Pratt  History of KMP string matching algorithm The algorithm was conceived inn 1970 by Donald Knuth and Vaughan Pratt and independently by James H. Morris. The three published it jointly in 1977. Before learn about KMP algorithm there are two things to learn,                      1. Prefix                       A string ω is a prefix of a string x, denoted w ⊏  x,                           if x =  ωy for some string y € Σ* and                            | ω | <= |x|                           e.g. ab ⊏ abcca     ...

👉How it works????? ♦Each character in pattern has a state. ♦ Each match sends the automaton into a new state ♦If all the characters in the pattern has been matched, the     automaton enters the accepting state.  ♦Otherwise, the automaton will return to a suitable state according to the current state and the input  character such that this returned state reflects the maximum advantage we can take from the       previous 👉 P reprocessing of pattern lets try example.... pattern= "ababc" lets make state transition table 1)Get the alphabet of pattern    alphabet of pattern  ={a,b,c} 2)Get the length of the pattern=5 lets draw the table.    1) 2) consider pattern lets fill "s0" column a      →      a     its match so value = 1 a     →     b     its doesn't  m...

Boyer Moore String Search Algorithm Boyer-Moore string search algorithm was developed by Robert S. Boyer and J Strother Moore in 1977. Concept of Boyer-Moore Algorithm Scan From right to left Bad character rule Good Suffix shift rule There is a preprocess in this algorithm. It's create a table with last occurrence of  pattern characters Example :                  Pattern : a b a c a b                               0 1 2 3 4 5                                     Table Note: If character not in pattern ,                                                T[i] = -1 Look at the table and find the last occurrence  "a" ( T[i] ...