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#include <stdio.h>
void encrypte(char current_char, char *key);
int main(int argc, char *argv[])
{

	if (argc <= 1 || argc > 2) {
		return 0;
	}

	char *substituted_alphabet = argv[1];
	char current_char;

	printf("Enter text:\n");

	while((current_char = getchar()) != EOF) {
		encrypte(current_char, substituted_alphabet);
	}

	return 0;
}

void encrypte(char current_char, char *key) {
	char result_char;
	int index = 0;

	if (current_char >= 'A' && current_char <= 'Z') {
			index = current_char - 'A';
			result_char = key[index] - 'a' + 'A';
	} 
	else if(current_char >= 'a' && current_char <= 'z') {
		index = current_char - 'a';
		result_char = key[index];
	} 
	else {
		result_char = current_char;
	}

	putchar(result_char);

}