C++ Programming Code Examples
C++ > Strings Code Examples
Repeatedly Search the Same Text (such as Bible by building a Data Structure)
/* Repeatedly Search the Same Text (such as Bible by building a Data Structure)
This C++ program performs naive string matching without using any specific library functions. A text and a pattern is given as input. The pattern is searched for in the text and all instances of the pattern are given as output. */
//enter string without spaces
#include<iostream>
#include<string.h>
using namespace std;
int main()
{
char org[100], dup[100];
int i, j, k = 0, len_org, len_dup;
cout << "NOTE:Strings are accepted only till blank space.";
cout << "\nEnter Original String:";
fflush(stdin);
cin >> org;
fflush(stdin);
cout << "Enter Pattern to Search:";
cin >> dup;
len_org = strlen(org);
len_dup = strlen(dup);
for (i = 0; i <= (len_org - len_dup); i++)
{
for (j = 0; j < len_dup; j++)
{
//cout<<"comparing '"<<org[i + j]<<"' and '"<<dup[j]<<"'.";
if (org[i + j] != dup[j])
break;
}
if (j == len_dup)
{
k++;
cout << "\nPattern Found at Position: " << i;
}
}
if (k == 0)
cout << "\nError:No Match Found!";
else
cout << "\nTotal Instances Found = " << k;
return 0;
}
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