Sum of Prefix Scores of Strings - Problem

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

/**
 * Calculates the score for each word based on how many words in the list
 * share its prefixes.
 */
int* solution(char** words, int wordsSize, int* returnSize) {
    *returnSize = wordsSize;
    int* answer = (int*)malloc(wordsSize * sizeof(int));
    
    for (int i = 0; i < wordsSize; i++) {
        long long totalScore = 0;
        int wordLen = strlen(words[i]);
        
        // Check each prefix of the current word
        // j is the length of the prefix
        for (int j = 1; j <= wordLen; j++) {
            int count = 0;
            
            // Count how many words start with this specific prefix
            for (int k = 0; k < wordsSize; k++) {
                // strncmp returns 0 if the first j characters match
                if (strncmp(words[i], words[k], j) == 0) {
                    count++;
                }
            }
            totalScore += count;
        }
        
        answer[i] = (int)totalScore;
    }
    
    return answer;
}

int main() {
    char line[10000];
    if (!fgets(line, sizeof(line), stdin)) return 0;
    
    // Array to store pointers to words
    char* words[1005]; 
    int wordsSize = 0;
    
    // --- Parsing Logic ---
    // The input format is ["word1", "word2"]
    // We use strtok to split by comma
    char* token = strtok(line, ",");
    
    while (token != NULL) {
        // 1. Trim leading characters: '[', '"', space
        while (*token == '[' || *token == '"' || *token == ' ') {
            token++;
        }
        
        // 2. Trim trailing characters: ']', '"', space, newline
        int len = strlen(token);
        while (len > 0 && (token[len - 1] == ']' || token[len - 1] == '"' || 
                           token[len - 1] == ' ' || token[len - 1] == '\n')) {
            token[len - 1] = '\0';
            len--;
        }
        
        // 3. Store the clean word
        if (len > 0) {
            words[wordsSize] = (char*)malloc(len + 1);
            strcpy(words[wordsSize], token);
            wordsSize++;
        }
        
        token = strtok(NULL, ",");
    }
    
    // --- Run Solution ---
    int returnSize;
    int* result = solution(words, wordsSize, &returnSize);
    
    // --- Print Result ---
    printf("[");
    for (int i = 0; i < returnSize; i++) {
        printf("%d", result[i]);
        if (i < returnSize - 1) printf(",");
    }
    printf("]\n");
    
    // --- Cleanup ---
    free(result);
    for (int i = 0; i < wordsSize; i++) {
        free(words[i]);
    }
    
    return 0;
}