#include <iostream>
#include <cstring>
int char_to_int(char *c) {
	int value = 0;
	int sign = 1;
	if(*c == '-') {
		sign = -1;
		c++;
	}
	while(*c != '\0') {
		value *= 10;
		value += *c - '0'; 
		c++;
	}
	return value * sign;
}
int main(int argc, char *argv[]) {
	if(argc != 3) {
		throw std::invalid_argument("Wrong number of parameters! Run like this: \"caeser x texthere\" where X is the desired shift amount");
	}
	int inputLength = strlen(argv[2]);
	int shift = char_to_int(argv[1]);
	while (shift < 0) {
		shift += 26;
	}
	char *output = (char*) malloc(inputLength);
	for(int i = 0; i < inputLength; i++) {
		int cVal = argv[2][i];
		int rStart;
		if(cVal >= 'A' && cVal <= 'Z') {
			rStart = 'A';
		}
		else if(cVal >= 'a' && cVal <= 'z'){
			rStart = 'a';
		}
		else {
			output[i] = cVal;
			continue;
		}
		int rVal = cVal - rStart;
		rVal = (rVal + shift) % 26;
		output[i] = rVal + rStart;
	}
	std::cout << output << '\n';
	free(output);
	return 0;
}