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POHashtable searching, and command prompt weird error
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2012-08-31T02:06:37.147
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I'm trying to search through a hash table, and I'm having some problems. My code compiles, but there's something wrong with it. I'm not quite sure what. When I ran it at the command prompt, and passed the file to the program. I'm having some problems with the searching 0 insincere <pre><code>struct htablerec { char **key; int *frequencies; int num_keys; int capacity; }; static unsigned int htable_word_to_int(char *word) { unsigned int result = 0; while (*word != '\0') { result = (*word++ + 31 * result); } return result; } int htable_insert(htable h, char *str) { int i; /*convert string to integer*/ unsigned int index = htable_word_to_int(str); /*calculate index to insert into hash table*/ int remainder = index%h->capacity; /*once calculated position in the hash table, 3 possibilities occur*/ /*no string in this positon, copy string to that position, increment number of keys, return 1*/ if (h->key[remainder] == NULL) { char *key = emalloc(strlen(str) + 1); strcpy(key, str); h->key[remainder] = key; h->frequencies[remainder] = 1; h->num_keys++; return 1; } /*the exact same string is at the position, increment frequency at that position, return frequency*/ if (strcmp(str, h->key[remainder]) == 0) { h->frequencies[remainder]++; return h->frequencies[remainder]; }/*a string is at that position, but it isnt the rightone, keep moving along the array until you find either an open space or the string you are looking for*/ if (h->key[remainder] != NULL && strcmp(str, h->key[remainder]) != 0) { /*you may need to wrap back around to the beginning of the table, so each time you add,to the position you should also mod by the table capacity.*/ for (i = 0; i < h->capacity; i++) { /*no string in this positon, copy string to that position, increment number of keys*/ if (h->key[remainder] == NULL) { char *key = emalloc(strlen(str) + 1); strcpy(key, str); h->key[remainder] = key; h->frequencies[remainder] = 1; h->num_keys++; } /*if you find the string you were looking for, increment the frequency at the position and return the frequency*/ if (strcmp(str, h->key[remainder]) == 0) { h->frequencies[remainder]++; return h->frequencies[remainder]; } if (h->key[remainder] != NULL && h->capacity == i) { i = 0; } } } /*if you have kept looking for an open space but there isnt one, the hash table must fu*/ return 0; } int htable_search(htable h, char *str) { /*create an initialise, a value to hold the number of collisions we have when looking for our key*/ int collisions = 0; unsigned int index = htable_word_to_int(str); /*calculate the position at which we should start looking for our key*/ int remainder = index%h->capacity; /*while there is an item at that position, but it isn't the key, and we haven't yet checked the entire hash table*/ while (h->key[remainder] != NULL && strcmp(str, h->key[remainder]) != 0 && h->key[remainder] != h->key[h->capacity]) { /*increment our position to look for the next cell*/ h->key[remainder]++; /*increment the number of collisions we've had so far*/ collisions++; } /*if our number of collisions == the hashtable capacity*/ if(collisions == h->capacity) { /*then out hashtable was full, did not contain our key, so we should return 0*/ return 0; } else { /*else return the frequency at our final position*/ return h->frequencies[h->capacity]; } } #include <stdio.h> #include <stdlib.h> #include "mylib.h" #include "htable.h" int main(void) { htable h = htable_new(113); char word[256]; char op; /*We must have a space before the %c*/ while(2 == scanf(" %c %255s", &op, word)) { if ('+' == op) { htable_insert(h, word); } else if ('?' == op) { printf("%d %s\n", htable_search(h, word), word); } } htable_free(h); return EXIT_SUCCESS; } </code></pre> I have included the mylib.c above. <pre><code>+ sociable + galleries + Russia + screamer + thickness + combed + escorted + revocable + digressed + Malawi + infringing + onslaught + files + kidded + unsound + tied + Ottawa + puzzles + build + necrosis + admire + cupful + brokers + segregation + Capet + Georges + bran + binders + zebras + contented + keypad + snowily + replaced + dominating + outright + Latinizers + invalidity + wakes + diversification + Riemannian + leadings + rhythmically + gentler + swarthy + disconnects + factoring + sequences + tiring + attendances + unloaded ? insincere ? constants ? unordered ? Toland ? butterfly ? suburban ? overtone ? Hauser ? numbers ? disadvantageous ? saintly ? Dutton ? homomorphic ? corporation ? climaxes ? dietitian ? manifestly ? greyest ? challenge ? tentacle ? Bernice ? bottle ? involve ? resisted ? wholesale ? trustworthiness ? Poole ? fourfold ? relentlessly ? fittingly ? doctorates ? cowlick ? Missoula ? curtsy ? calmness ? reallocate ? bossed ? scarce ? catheters ? regained ? autographing ? unobservable ? apprise ? lancer ? chicken ? crunches ? scrambled ? reared ? pealing ? violate ? sociable ? galleries ? Russia ? screamer ? thickness ? combed ? escorted ? revocable ? digressed ? Malawi ? infringing ? onslaught ? files ? kidded ? unsound ? tied ? Ottawa ? puzzles ? build ? necrosis ? admire ? cupful ? brokers ? segregation ? Capet ? Georges ? bran ? binders ? zebras ? contented ? keypad ? snowily ? replaced ? dominating ? outright ? Latinizers ? invalidity ? wakes ? diversification ? Riemannian ? leadings ? rhythmically ? gentler ? swarthy ? disconnects ? factoring ? sequences ? tiring ? attendances ? unloaded </code></pre> This is the contents of the file i'm passing in. My insert method works, but if that is needed, i can include that too.
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Hashtable searching, and command prompt weird error
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