The problem of “Hash Tables: Ransom Notes” – C Source code

Harold is a kidnapper who wrote a ransom note, but now he is worried it will be traced back to him through his handwriting. He found a magazine and wants to know if he can cut out whole words from it and use them to create an untraceable replica of his ransom note. The words in his note are case-sensitive and he must use only whole words available in the magazine. He cannot use substrings or concatenation to create the words he needs.

Given the words in the magazine and the words in the ransom note, print Yes if he can replicate his ransom note exactly using whole words from the magazine; otherwise, print No.

For example, the note is “Attack at dawn”. The magazine contains only “attack at dawn”. The magazine has all the right words, but there’s a case mismatch. The answer is NO.

https://www.hackerrank.com/challenges/ctci-ransom-note/

#include <assert.h>
#include <limits.h>
#include <math.h>
#include <stdbool.h>
#include <stddef.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

char* readline();
char** split_string(char*);

bool list_contains(char * word, char** list, int count)
{
    for(int i=0;i<count;i++)
        if(strcmp(word,list[i])==0)
        {
            strcpy(list[i],"");
            return true;
        }
    return false;
}

// Complete the checkMagazine function below.
void checkMagazine(int magazine_count, char** magazine, int note_count, char** note) {

    bool result = true;
    for(int i=0;i<note_count;i++)
    {
        if(list_contains(note[i],magazine,magazine_count) == false)
        {
            result = false;
            break;
        }
    }
    printf(result == true ? "Yes" : "No");
}

int main()
{
    char** mn = split_string(readline());

    char* m_endptr;
    char* m_str = mn[0];
    int m = strtol(m_str, &m_endptr, 10);

    if (m_endptr == m_str || *m_endptr != '\0') { exit(EXIT_FAILURE); }

    char* n_endptr;
    char* n_str = mn[1];
    int n = strtol(n_str, &n_endptr, 10);

    if (n_endptr == n_str || *n_endptr != '\0') { exit(EXIT_FAILURE); }

    char** magazine_temp = split_string(readline());

    char** magazine = malloc(m * sizeof(char*));

    for (int i = 0; i < m; i++) {
        char* magazine_item = *(magazine_temp + i);

        *(magazine + i) = magazine_item;
    }

    int magazine_count = m;

    char** note_temp = split_string(readline());

    char** note = malloc(n * sizeof(char*));

    for (int i = 0; i < n; i++) {
        char* note_item = *(note_temp + i);

        *(note + i) = note_item;
    }

    int note_count = n;

    checkMagazine(magazine_count, magazine, note_count, note);

    return 0;
}

char* readline() {
    size_t alloc_length = 1024;
    size_t data_length = 0;
    char* data = malloc(alloc_length);

    while (true) {
        char* cursor = data + data_length;
        char* line = fgets(cursor, alloc_length - data_length, stdin);

        if (!line) {
            break;
        }

        data_length += strlen(cursor);

        if (data_length < alloc_length - 1 || data[data_length - 1] == '\n') {
            break;
        }

        alloc_length <<= 1;

        data = realloc(data, alloc_length);

        if (!line) {
            break;
        }
    }

    if (data[data_length - 1] == '\n') {
        data[data_length - 1] = '\0';

        data = realloc(data, data_length);
    } else {
        data = realloc(data, data_length + 1);

        data[data_length] = '\0';
    }

    return data;
}

char** split_string(char* str) {
    char** splits = NULL;
    char* token = strtok(str, " ");

    int spaces = 0;

    while (token) {
        splits = realloc(splits, sizeof(char*) * ++spaces);

        if (!splits) {
            return splits;
        }

        splits[spaces - 1] = token;

        token = strtok(NULL, " ");
    }

    return splits;
}