تحديات برمجيةالتحدي الثاني - حل التمرين الرابع بلغة C

#include <stdio.h>
#include <string.h>
#define MAX_SIZE 1000

void main() {
    
    char S1[MAX_SIZE];
    char S2[MAX_SIZE];
    char S3[MAX_SIZE];
    char * S4 = (char*)malloc(sizeof(MAX_SIZE) + 1);
    char * concatenated = (char*)malloc(sizeof(MAX_SIZE) + 1);
    char * temp = (char*)malloc(sizeof(MAX_SIZE) + 1);
    
    int counter = 0;
    int concateIndex = 0;
    
    printf("Enter S1: ");
     gets(S1);
    
    printf("Enter S2: ");
    gets(S2);
    
    printf("Enter S3: ");
    gets(S3);
    
    printf("---------------------------------------\n");
    
    // Part 1
    for (int i = 0; i < strlen(S1); i++)
    {
        concatenated[concateIndex] = S1[i];
        concateIndex++;
    }
    for (int i = 0; i < strlen(S2); i++)
    {
        concatenated[concateIndex] = S2[i];
        concateIndex++;
    }
    concatenated[concateIndex] = '\0';
    
    printf("The concatenation of S1 and S2 is equal S3? ");
    printf("%s\n", (strcmp(S3, concatenated) == 0)? "True": "False");
    
    // Part 2
    printf("S1 is part of S2 or S1=S2? ");
    printf("%s\n", (strstr(S2, S1) != NULL)? "True": "False");
    
    // Part 3
    if (strlen(S1) > strlen(S2))
    {
        int index = 0;
        for (int i = 0; i < strlen(S2); i++)
        {
            S4[index] = S2[i];
            index++;
        }
        
        for (int i = 0; i < strlen(S1); i++)
        {
            S4[index] = S1[i];
            index++;
        }
        
        S4[index] = '\0';
    } 
        
    // Part 4
    if (strlen(S2) > strlen(S1))
    {
        int index = 0;
        for (int i = 0; i < strlen(S1); i++)
        {
            S4[index] = S1[i];
            index++;
        }
        
        for (int i = 0; i < strlen(S2); i++)
        {
            S4[index] = S2[i];
            index++;
        }
        
        S4[index] = '\0';
    } 
    
    // Part 5
    printf("S2 is part of the second half of S1? ");
    for (int i = strlen(S1) / 2; i <= strlen(S1); i++)
    {
        temp[counter] = S1[i];
        counter++;
    }
    temp[counter] = '\0';
    printf("%s\n", (strstr(temp, S2) != NULL)? "True": "False");
    
    // Part 6
    printf("The first half characters of S1 are: ");
    for (int i = 0; i < strlen(S1) / 2; i++)
    {
        printf("%c", S1[i]);
    }
}