hdu 4950 Monster

Monster

Time Limit: 2000/1000 MS (Java/Others) Memory Limit: 65536/65536 K (Java/Others)
Total Submission(s): 590 Accepted Submission(s): 238


Problem Description Teacher Mai has a kingdom. A monster has invaded this kingdom, and Teacher Mai wants to kill it.

Monster initially has h HP. And it will die if HP is less than 1.

Teacher Mai and monster take turns to do their action. In one round, Teacher Mai can attack the monster so that the HP of the monster will be reduced by a. At the end of this round, the HP of monster will be increased by b.

After k consecutive round's attack, Teacher Mai must take a rest in this round. However, he can also choose to take a rest in any round.

Output "YES" if Teacher Mai can kill this monster, else output "NO".
Input There are multiple test cases, terminated by a line "0 0 0 0".

For each test case, the first line contains four integers h,a,b,k(1<=h,a,b,k <=10^9).
Output For each case, output "Case #k: " first, where k is the case number counting from 1. Then output "YES" if Teacher Mai can kill this monster, else output "NO".

Sample Input

5 3 2 2
0 0 0 0

Sample Output

Case #1: NO

Source 2014 Multi-University Training Contest 8

題解及代碼：

簽到題，不多講，分成三個階段模擬，第一階段，看是否能一下就把怪物殺死；第二階段，進行到第k回合，假設我進行攻擊，怪物未回血，看是否能將其殺死；

第三階段，進行玩第k+1回合，看這幾個回合下來怪物是否掉血了。

#include 
#include 
using namespace std;

int main()
{
    int cas=1;
    long long h,m,n,t;
    while(scanf("%I64d%I64d%I64d%I64d",&h,&m,&n,&t)!=EOF)
    {
        if(!h&&!m&&!n&&!t)
            break;
        if(m<=n)
        {
            if(h<=m)
            {
                printf("Case #%d: YES\n",cas++);
            }
            else
            {
                printf("Case #%d: NO\n",cas++);
            }
            continue;
        }
        if(m*t-n*(t-1)>=h)
        {
            printf("Case #%d: YES\n",cas++);
        }
        else
        {
           if(m*t-n*(t+1)>=1)
            printf("Case #%d: YES\n",cas++);
           else
            printf("Case #%d: NO\n",cas++);
        }
    }
    return 0;
}