#include #include void main(void){ char eMail[1000000] = "a"; scanf("%s",eMail); bool atSignFlg = false; int i = 0 ; while(eMail[i] != '\0'){ if(!atSignFlg){ if(eMail[i] != '('){ printf("%c",eMail[i]); }else{ atSignFlg = true; } }else{ if(eMail[i] == ')'){ atSignFlg = false; printf("@"); } } i++; } }