题解

#include <stdio.h>
#include <string.h>

int main() {
    int n;
    char original[100010];
    scanf("%d", &n);
    getchar();
    fgets(original, 100010, stdin);
    size_t len = strlen(original);
    if (len > 0 && original[len - 1] == '\n') {
        original[len - 1] = '\0';
    }
    for (int i = 0; original[i] != '\0'; i++) {
        if (original[i] >= 'a' && original[i] <= 'z') {
            original[i] = 'a' + (original[i] - 'a' + n) % 26;
        }
    }
    printf("%s\n", original);
    
    return 0;
}