fixed c++ style comments to compile against pure c

src/3_n_a_xor_encryption.c

@@ -1 +1 @@
-#include <stdio.h>
#include <string.h>

#define MAX_LENGTH 31 // 30 characters + '\0' termination
#define SALT 15

int main() {
	char input[MAX_LENGTH];
	int offset = 0;
	char character;

	// prompt for input
	printf("Please enter message: ");
	while (offset + 1 < MAX_LENGTH && (character = getchar()) != '\n') {
		input[offset++] = character;
	}
	input[offset] = '\0';

	// encrypt message
	for (offset = 0; offset < strlen(input); offset++) {
		input[offset] ^= SALT;
	}
	printf("Encrypted message: %s\n", input);

	// decrypt message
	for (offset = 0; offset < strlen(input); offset++) {
		input[offset] ^= SALT;
	}
	printf("Decrypted message: %s\n", input);

	return 0;
}
+#include <stdio.h>
#include <string.h>

#define MAX_LENGTH 31 /*  30 characters + '\0' termination */
#define SALT 15

int main() {
	char input[MAX_LENGTH];
	int offset = 0;
	char character;

	/* prompt for input */
	printf("Please enter message: ");
	while (offset + 1 < MAX_LENGTH && (character = getchar()) != '\n') {
		input[offset++] = character;
	}
	input[offset] = '\0';

	/* encrypt message */
	for (offset = 0; offset < strlen(input); offset++) {
		input[offset] ^= SALT;
	}
	printf("Encrypted message: %s\n", input);

	/* decrypt message */
	for (offset = 0; offset < strlen(input); offset++) {
		input[offset] ^= SALT;
	}
	printf("Decrypted message: %s\n", input);

	return 0;
}

src/3_n_c_userdb.c

@@ -17,7 +17,7 @@ int main() {
 	int count, offset;
 
 	for (offset = 0, count = 0; offset < MAX_ACCOUNTS; offset++, count++) {
-		printf("Should this user be activated? (0/1/-1): ");  // -1 for break input
+		printf("Should this user be activated? (0/1/-1): ");  /* -1 for break input */
 		fgets(input_buffer, BUFFER_SIZE, stdin);
 		users[offset].active = atoi(input_buffer);
 		if (users[offset].active == -1) {