[HDU - 1276]士兵队列训练问题

 1 #include <bits/stdc++.h>
 2 #define maxn 5000 + 10
 3 int main(){
 4     int in;
 5     while (~scanf("%d", &in)){
 6         while (in--){
 7             int left, a[maxn], b[maxn], c[maxn], num;
 8             int flag = 1;
 9             scanf("%d", &num);
10             left = num;
11             int r = 0;
12             for(int i = 0; i < num; i++)
13                 a[i] = i+1, b[i] = i, c[i] = 1;
14 
15             if(left <= 3){
16                 for (int i = 0; i < left; i++){
17                     if(r) printf(" %d", a[i]);
18                     else printf("%d", a[i]);
19                     r = 1;
20                 }printf("\n");
21             }else {
22                 int j = 0;
23                 for (int i = 0; i < num; i++)
24                     if(c[i]) b[j++] = i;
25 
26                 while (left > 3){
27                     int j = 0;
28                     if (flag){
29                         for(int i = 1; i < left; i+=2)
30                             c[b[i]] = 0;
31                         left =left - left / 2;
32                     } else {
33                         for(int i = 2; i < left; i+=3)
34                             c[b[i]] = 0;
35                         left = left - left / 3;
36                     }
37                     flag = !flag;
38                     for(int i = 0; i < num; i++) if(c[i]) b[j++] = i;
39                     r = 0;
40                 }
41                 for(int i = 0; i < left; i++)
42                 {
43                     if(r) printf(" %d", a[b[i]]);
44                     else printf("%d", a[b[i]]);
45                     r = 1;
46                 }
47                 printf("\n");
48             }
49         }
50     }
51     return 0;
52 }