UVA 11729 Commando War

Commando War

There is a war and it doesn't look very promising for your country. Now it's time to act. You have a commando squad at your disposal and planning an ambush on an important enemy camp located nearby. You have soldiers in your squad. In your master-plan, every single soldier has a unique responsibility and you don't want any of your soldier to know the plan for other soldiers so that everyone can focus on his task only. In order to enforce this, you brief every individual soldier about his tasks separately and just before sending him to the battlefield. You know that every single soldier needs a certain amount of time to execute his job. You also know very clearly how much time you need to brief every single soldier. Being anxious to finish the total operation as soon as possible, you need to find an order of briefing your soldiers that will minimize the time necessary for all the soldiers to complete their tasks. You may assume that, no soldier has a plan that depends on the tasks of his fellows. In other words, once a soldier  begins a task, he can finish it without the necessity of pausing in between.

Input

There will be multiple test cases in the input file. Every test case starts with an integer N (1<=N<=1000), denoting the number of soldiers. Each of the following N lines describe a soldier with two integers B (1<=B<=10000) J (1<=J<=10000)seconds are needed to brief the soldier while completing his job needs seconds. The end of input will be denoted by a case with N =0 . This case should not be processed.

Output

For each test case, print a line in the format, “Case X: Y”, where X is the case number & Y is the total number of seconds counted from the start of your first briefing till the completion of all jobs.

 

Sample Input                                               Output for Sample Input

3

2 5

3 2

2 1

3

3 3

4 4

5 5

0

Case 1: 8

Case 2: 15

 



【题目翻译】:


【思路】:

贪心算法:处理时间长的先交代。按照J从大到小的顺序给任务排序,依次交代。交代时间不用管。

【代码】:

 1 #include<queue>
 2 #include<math.h>
 3 #include<stdio.h>
 4 #include<string.h>
 5 #include<iostream>
 6 #include<algorithm>
 7 using namespace std;
 8 #define N 123456
 9 #define M 1234
10 
11 struct node
12 {
13     int a,b;
14 }st[10004];
15 int n;
16 
17 int cmp(node x,node y)
18 {
19     if(x.b!=y.b)return x.b>y.b;
20 }
21 int main()
22 {
23     int tt=1;
24     while(~scanf("%d",&n)&&n)
25     {
26         for(int i=0;i<n;i++)
27             scanf("%d%d",&st[i].a,&st[i].b);
28         sort(st,st+n,cmp);
29         int sum=0;
30         int sum2=0;
31         for(int i=0;i<n;i++)
32         {
33             sum+=st[i].a;
34             sum2=max(sum2,sum+st[i].b);
35         }
36         printf("Case %d: %d
",tt++,sum2);
37     }
38     return 0;
39 }
There is a war and it doesn't look very promising for your country. Now it's time to act. You
have a commando squad at your disposal and planning an ambush on an important enemy camp
located nearby. You have
N
soldiers in your squad. In your master-plan, every single soldier has a
unique responsibility and you don't want any of your soldier to know the plan for other soldiers so that
everyone can focus on his task only. In order to enforce this, you brief every individual soldier about
his tasks separately and just before sending him to the battle eld. You know that every single soldier
needs a certain amount of time to execute his job. You also know very clearly how much time you
need to brief every single soldier. Being anxious to nish the total operation as soon as possible, you
need to nd an order of brie ng your soldiers that will minimize the time necessary for all the soldiers
to complete their tasks. You may assume that, no soldier has a plan that depends on the tasks of his
fellows. In other words, once a soldier begins a task, he can nish it without the necessity of pausing
in between.
Input
There will be multiple test cases in the input le. Every test case starts with an integer
N
(1

N

1000), denoting the number of soldiers. Each of the following
N
lines describe a soldier with two
integers
B
(1

B

10000) &
J
(1

J

10000).
B
seconds are needed to brief the soldier while
completing his job needs
J
seconds. The end of input will be denoted by a case with
N
= 0. This case
should not be processed.
Output
For each test case, print a line in the format, `
Case
X
:
Y
', where
X
is the case number &
Y
is the
total number of seconds counted from the start of your rst brie ng till the completion of all jobs.
SampleInput
3
2 5
3 2
2 1
3
3 3
4 4
5 5
0
SampleOutput
原文地址:https://www.cnblogs.com/wmxl/p/4705026.html