java写的，ac了 public static void main(String[] args) {         Scanner cin = new Scanner(System.in);         while (cin.hasNextInt()) {             int a = cin.nextInt();             int b = cin.nextInt();             int k = cin.nextInt();             int v = cin.nextInt();             int res=0;             while(a>0){                 if(b>=k-1){                     b=b-(k-1);                     a-=k*v;                 }else if(b<(k-1) && b!=0){                     a-=v*(b+1);                     b=0;                 }else{                     a-=v;                 }                 res++;             }             System.out.println(res);         }     }