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Anyone knows what I did wrong in this program?

I am trying to encrypt() and decrypt() strings in the parentheses using this program, but it keeps encrypting and decrypting the closing parentheses and the words after.

        if (strncmp(input, "encrypt", 7) == 0) {
            char *textToEncrypt = input + 8;  // Skip "encrypt" and the space
            if (*textToEncrypt == '(') {
                textToEncrypt++;  // Skip the opening parenthesis
                char *closingParenthesis = strchr(textToEncrypt, ')');
                if (closingParenthesis) {
                    *closingParenthesis = '\0';  // Terminate the string at the closing parenthesis
                }
            }
            encrypt(textToEncrypt);
        }

void encrypt(char text[]) {
    char encryptedChar;
    char array[1000] = "";
    for (int i = 0; i < strlen(text); i++) {
        encryptedChar = text[i] + 5;
        //printf("\nThe ASCII Value of %c is %u\n", encryptedChar, (unsigned char)encryptedChar);
        strncat(array, &encryptedChar, 1);
    }
    printf("%s\n", array);
    memset(array, 0, sizeof array);
}

The decrypt code is similar to encrypt just reversed.

Result
Enter command: encrypt(hi)
mn.
Enter command: decrypt(mn)
hi$
Enter command: encrypt(hi
mn
Enter command: decrypt(mn
hi
Enter command: encrypt(hi)ghjkl
mn.lmopq
Enter command: decrypt(mn)ghjk
hi$bcef
Enter command:

How do I make it only encrypt/decrypt the words in the parentheses?

Solution

    1. encrypt(textToEncrypt); should be immediately after *closingParenthesis = '\0' (inside the innermost if).

    2. input + 8 should be input + 7. The fact that you used 7 on the previous line should have been a tip! Maybe you should avoid using "magic numbers" and derive those constants...