#include <stdio.h>

int main(void) {
	char in[9999] = {'\0'};
	char out[9999] = {'\0'};
	int i = 0, tmp;
	
	scanf("%s", in);
	
	while(in[i] != '\0'){
		tmp = in[i] - i - 'A' - 1;
		while(tmp < 0){ tmp += 26; }
		out[i] = 'A' + tmp % 26;
		i++;
	}
	
	printf("%s\n", out);
	return 0;
}