oj 1031 random permutation

 1 #include<iostream>
 2 #include<cstdlib>
 3 #include<ctime>
 4 using namespace std;
 5 int seed=time(0);
 6 int b[50]={0};
 7 int test(int b[],int i,int temp)
 8 {
 9     for (int j=0;j<i;j++)
10     {
11         if (b[j]==temp) return -1;
12     }
13     return 0;
14 }
15 void give_test(int b[],int temp,int i,int n)
16 {
17     seed++;
18     srand(seed);
19     temp=rand()%n;
20     if (test(b,i,temp)==-1) 
21     {
22         seed++;
23         give_test(b,temp,i,n);
24     }
25     else b[i]=temp;
26 }
27 void random_permute(int a[],int n)
28 {
29     srand(seed);
30     b[0]=rand()%n;
31     int temp=0;
32     for (int i=1;i<n;i++)
33     {
34         give_test(b,temp,i,n);
35     }
36     for (int i=0;i<n;i++)
37     cout<<a[b[i]]<<" ";
38 }
39 int main(int argc,char *argv[])
40 {
41     int n;
42     cin>>n;
43     int a[50];
44     for (int i=0;i<n;i++)
45         cin>>a[i];
46     random_permute(a,n);
47     cout<<n<<endl;
48     return 0;
49 }