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POarray of strings printing wrong values
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copied!<p>I trying to make a program that calculates proper prefixes and proper suffixes , and then compare the sets , and then return the array containing values representing number of matched pairs , This could be used later in KMP algorithm . But the problem is prefixes and suffixes array give wrong values . Even after appending a new element at new index, it replaces the all value in the array with the new element . </p> <pre><code>#include <stdio.h> #include <string.h> #include <stdlib.h> int* lps(char *,int ); int main() { char *pat = "abababca"; int *ptr ; ptr = lps(pat,strlen(pat)); printf("\n***LPS***\n"); } int * lps (char *p,int s) { char *prefixes[s] ; char *suffixes[s] ; char tmp1[s] , tmp2[s]; int i , j , k , c1 , c2 , c; for (i = 0 ; i < s ; i ++) { printf("\n\n*** --- Creating Prefixes and Suffixes for i = %d --- ***",i); c1 = 0 ; //create prefixes for (j = 0 ; j < i; j++) { for (k =0 ; k <= j; k++) { tmp1[k]=*(p+k); printf("\n *(p+%d)= %c , tmp1[%d]=%c",k,*(p+k),k,tmp1[k]); } tmp1[k]='\0'; printf("\nprefixes[0]:%s",prefixes[0]); prefixes[c1] = tmp1; //strcpy(prefixes[c1], tmp1); printf("\ncurrently added %s to prefixes at %d and prefixes[%d]= %s\n ",tmp1,c1,c1,prefixes[c1]); c1++; } //print prefixes for (k = 0; k<c1; k++) { printf("\tprefixes[%d] = %s",k,prefixes[k]); } printf("\n"); //create suffixes c2 = 0; for (j = 1 ; j <= i; j++) { for (k = j ; k <= i; k++) { tmp2[k-j] = *((p+k)); printf("\n *(p+%d)= %c , tmp2[%d]=%c",k,*(p+k),k-j,tmp2[k-j]); } tmp2[k-j]='\0'; suffixes[c2] = tmp2 ; // strcpy(suffixes[c2], tmp2); printf("\ncurrently added %s to suffixes at %d and suffixes[%d]= %s\n",tmp2,c2,c2,suffixes[c2]); c2++; } //prinf suffixes for (k = 0; k<c2; k++) { printf("\tsuffixes[%d] = %s",k,suffixes[k]); } printf("\n"); //compare the prefixes and suffixes c = 0 ; for (j = 0; j < c1; j++) { for(k=0 ; k < c2 ; k++) { printf("\nprefixes[%d] = %s , suffixes[%d] = %s\n ",j,prefixes[j],k,suffixes[k]); if (strcmp(prefixes[j], suffixes[k])==0) { c = c + 1 ; } } } } } </code></pre> <p>OUTPUT (Some part of OUTPUT) :-</p> <pre><code>prefixes[0] = ab prefixes[1] = ab //it should be prefixes[0] = a prefixes[1] = ab </code></pre>

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