Question

please implement this function by C language

Write a string compare function which returns 1 if the strings match for n characters starting at offset m, O if the strings don't match. You must check if m is within the length of both s and t. int submatch(char* s, char* t, int n, int m)

Answer 1

Below is the C language function:-

int submatch( char *s, char *t, int n, int m)

{

int l=0, k;

while( l < m)

{

if(s[l] == '\0' || t[l] == '\0') //then this means one of the string does not have length m

return 0; //Since no matching will be after index m

l++; //otherwise increment index l

}

while(s[l] != '\0' || t[l] != '\0') //we start with index following offset m, continue till one of the string does not end

{

if(s[l] != t[l]) //This means string does not match

return 0;

l++; //otherwise simply increment the index

}

if(s[l] == '\0' && t[l] =='\0') //This happens if both the strings s and t ends at the same time and being matched

return 1;

else

return 0;

}

Please comment for any clarification.