Delete all occurrences of pattern (pat) from a string (txt)
#include<stdio.h>
#include<string.h>
void main()
{
char
txt[30], pat[30];
int m, n;
int i, j, found = 0;
printf("\nEnter the main string:");
gets(txt);
printf("\nEnter the pattern to be searched: ");
gets(pat);
m = strlen(txt);
n = strlen(pat);
for(i=0;
i<=m-n; i++)
{
found
= 1;
for(j=0; j<n; j++)
{
if(txt[i+j]
!= pat[j])
{
found
= 0;
break;
}
}
if(found == 1)
{
/* If pattern is found then shift
all characters to left and decrement the string length */
for(j=i; j<m -n; j++)
{
txt[j]
= txt[j+n];
}
txt[j]
= '\0';
m = m - n;
}
}
if(found == 0)
printf("\nPattern not
found");
else
{
printf("\nAfter deleting pattern the
string is: ");
puts(txt);
}
}
Output:
Enter the main string: hello hii how hii
Enter the pattern to be searched:
hii
After deleting pattern the string is: hello how
Enter the main string: hello hii how hii
Enter the pattern to be searched: abc
Pattern not found
