【ACM菜逼解题报告】The Dragon of Loowater

The Dragon of Loowater

Once upon a time, in the Kingdom of Loowater, a minor nuisance turned into a major problem.

The shores of Rellau Creekin central Loowater hadalways been a prime breeding ground for geese. Due to the lack of predators, the geese population was out of control. The people of Loowater mostly kept clear of the geese.
Occasionally, a goose would attack one of the people, and perhaps bite off a finger or two, but in general, the people tolerated the geese as a minor nuisance.

One day, a freak mutation occurred, and one of the geese spawned a multi-headed fire-breathing dragon. When the dragon grew up, he threatened to burn the Kingdom of Loowater to a crisp. Loowater had a major problem.
The king was alarmed, and called on his knights to slay the dragon and save the kingdom. The knights explained: "To slay the dragon, we must chop off all its heads. Each knight can chop off one of the dragon's heads. The heads of the dragon are of different
sizes. In order to chop off a head, a knight must be at least as tall as the diameter of the head. The knights' union demands that for chopping off a head, a knight must be paid a wage equal to one gold coin for each centimetre of the knight's height."

Would there be enough knights to defeat the dragon? The king called on his advisors to help him decide how many and which knights to hire. After having lost a lot of money building Mir Park, the king wanted to minimize
the expense of slaying the dragon. As one of the advisors, your job was to help the king. You took it very seriously: if you failed, you and the whole kingdom would be burnt to a crisp!

Input Specification:

The input contains several test cases. The first line of each test case contains two integers between 1 and 20000 inclusive, indicating the number n of heads that the dragon has, and the number m of knights in the kingdom.
The next n lines each contain an integer, and give the diameters of the dragon's heads, in centimetres. The following m lines each contain an integer, and specify the heights of the knights of Loowater, also in centimetres. The last test case is followed by
a line containing: 0 0

Output Specification:

For each test case, output a line containing the minimum number of gold coins that the king needs to pay to slay the dragon. If it is not possible for the knights ofLoowater to slay the dragon, output the line: Loowater is doomed!

Sample Input:

2 3

5

4

7

8

4

2 1

5

5

10

0 0

Output for Sample Input:

11

Loowater is doomed!

此题先对heads和knights两数组进行排序，然后贪心，可用两种方式进行贪心处理：第一种，扫描heads数组；第二种，扫描knights数组。

注意特殊情况的判断。很久不敲，代码丑陋，望各路大神海涵。

附代码如下：

第一种

#include<cstdio>
#include<algorithm>

using namespace std;

#define MAXN 20000+5
#define MAXM 20000+5

int A[MAXN],B[MAXM];

int main(){
int n,m;
while(scanf("%d%d",&n,&m)==2&&n!=0&&m!=0){
for(int i=0;i<n;i++) scanf("%d",&A[i]);
for(int i=0;i<m;i++) scanf("%d",&B[i]);
sort(A,A+n);
sort(B,B+m);
int cur=0;
int count=0;
int i=0;
for(;i<n;i++,cur++){
while(A[i]>B[cur]&&cur<m)cur++;
if(cur>=m&&i<n){
printf("Loowater is doomed!\n");
break;
}
count+=B[cur];
}
if(i==n)printf("%d\n",count);
}
return 0;
}

第二种

#include<cstdio>
#include<algorithm>

using namespace std;

#define MAXN 20000+5
#define MAXM 20000+5

int A[MAXN],B[MAXM];

int main(){
int n,m;
while(scanf("%d%d",&n,&m)==2&&n!=0&&m!=0){
for(int i=0;i<n;i++) scanf("%d",&A[i]);
for(int i=0;i<m;i++) scanf("%d",&B[i]);
sort(A,A+n);
sort(B,B+m);
int cur=0;
int count=0;
for(int i=0;i<m;i++){
if(B[i]>=A[cur]){
count+=B[i];
if(++cur==n)break;
}
}
if(cur<n)printf("Loowater is doomed!\n");
else printf("%d\n",count);
}
return 0;
}