prob4.c

#include <stdio.h>

int main(int argc, char** argv) {
    int offset;
    char c;
    scanf("%d\n", &offset);
    while (scanf("%c", &c) != EOF && c != '\n') {
        printf("%c", 'A' + ((c - 'A' + offset) % 26));
    }
    return 0;
}