#include<cstdio> #include<cstring> char str[11111]; int main() { int n; scanf("%d", &n); getchar(); gets(str); char *pch; pch = strtok(str, " "); while(pch!=NULL){ char tmp[111]; int len; sprintf(tmp,"%s", pch); len = strlen(tmp); for(int i=0;i<len;i+=2){ if(tmp[i+1] !='\0'){ int ans = (tmp[i]-'a'+tmp[i+1]-'a' - n); if(ans < 0){ ans+=26; } printf("%c", ans%26 + 'a'); } } printf(" "); pch = strtok(NULL, " "); } return 0; }