/* file: simpleEncoding.c */
/* author: Benediktus Firstian Pradipta (b.f.pradipta@studnet.rug.nl) (S5241529)*/

/* Description:
Inputs a string of text and shifts character by a position relative to their order. Eg first character is shifted once.
Only letter characters are shifted, Uppercase characters remains Uppercase.
*/

#include <stdio.h>
#include <stdlib.h>

int main(int argc,char*agrv[]) {
	
char input;
// x=1 because it starts from the first position
int x=1;

// inputs characters untill a new line is entered
while((input=getchar())!='\n'){
    // to sort out the capital letter character from other special characters
	if (input >= 'A' && input  <= 'Z'){
	// Shifts the value of the input, after calculating how far away from 'Z' it is, and counts up from 'A'
		input = (((input + x - 'A')%26) + 'A');
    }
	// same code as the previous one but for lowercase letters
	else if ((input >= 'a' && input <= 'z')){
		input = (((input + x - 'a')%26) + 'a');
    }
	// adds a value to the x(as it goes to the next character)
    printf("%c", input);
	// prints the new value input, if character is not a letter it doesnt change
	x++;
}	
    printf("\n");
	return 0;
}