Based on String Processing

1. KMP Algorithm ... A simple and efficient string matching algorithm Click here to see the code

2. Ternary Search Tree...For String Storing and Matching and Traversing.... An Efficient Approach  Click here to see the code

3. Tries-String Storing and matching Program Using C language click here to see the code

Tries-String Storing and matching Program Using C language.

//A simple Tries implementation in C language, for alphabets.This program can store very efficiently strings and can be further used to find whether it exist or not.

#include<stdio.h>
#include<stdlib.h>
typedef struct TrieNode
{
char data;
int eos;
struct TrieNode *child[26];
}Trie;
Trie *Insertion(Trie *Root,char word[])
{
if(!word)
return Root;
 if(!Root)
 {
  Trie *newnode=(Trie*)malloc(sizeof(Trie));
  newnode->data=*word;
  newnode->eos=1;
  int i=0;
  for(i=0;i<26;i++)
  newnode->child[i]=NULL;


  if(*(word+1)<32)
   newnode->eos=0;
else
newnode->child[*(word+1)-97]=Insertion( newnode->child[*(word+1)-97],word+1);
   return newnode;
 }
  if(*(word+1)<32)
  Root->eos=0;
  else
  Root->child[*(word+1)-97]=Insertion(Root->child[*(word+1)-97],word+1);
 
return Root;
}

int Search(Trie *Root,char word[])
{   if(!Root) return -1;
    if(!word) return -1;
    if(!*word)return -1;

if(Root->data==*word)
{
  printf("%c  %s\n",Root->data,word);
 if(Root->eos==0&& *(word+1)<32)
   {
   return 1;
   }
  else if(*(word+1)<32)
  {
  return -1;
  }
  else
 return Search(Root->child[*(word+1)-97],word+1);
    }
    else
     {
return -1;
     }
}


int main(void)
{
Trie *Root=(Trie*)malloc(sizeof(Trie));
char Text[10];
char Pattern[10];
int i=0;

for(i=0;i<26;i++)
Root->child[i]=NULL;
printf("Enter the text\n");
int j=0;
for(i=0;i<3;i++)
{
j=0;
scanf("%s",Text);
for(j=0;Text[j];j++)  // capital and small letter conversion into capital or invalid results
{
if(Text[j]<97||Text[j]>122)
 {
  if((Text[j]+32)>122||(Text[j]+32)<97)
  {
    printf("Invalid String Try again only Alphabet are allowed\n");
  break;
  }
  else
   {
   Text[j]=Text[j]+32;
        Root->child[*Text-97]=Insertion(Root->child[*Text-97],Text);
        }
      }
      else
      Root->child[*Text-97]=Insertion(Root->child[*Text-97],Text);
}
}

printf("\nEnter the searching word\n");
scanf("%s",Pattern);
for(j=0;Pattern[j];j++)
{
if(Pattern[j]<97)
Pattern[j]=Pattern[j]+32;
}
int k;
k=Search(Root->child[*Pattern-97],Pattern);
if(k==1)printf("\nExist");
else
printf("\nno such word exist");
return 0;
}