uva1620 Lazy Susan

留坑(p.256)

什么找规律啊 坑爹

 

 1 #include<cstdio>
 2 #include<cstring>
 3 #include<cstdlib>
 4 #include<algorithm>
 5 #include<iostream>
 6 
 7 using namespace std;
 8 
 9 void setIO(const string& s) {
10     freopen((s + ".in").c_str(), "r", stdin);
11     freopen((s + ".out").c_str(), "w", stdout);
12 }
13 template<typename Q> Q read(Q& x) {
14     static char c, f;
15     for(f = 0; c = getchar(), !isdigit(c); ) if(c == '-') f = 1;
16     for(x = 0; isdigit(c); c = getchar()) x = x * 10 + c - '0';
17     if(f) x = -x;
18     return x;
19 }
20 template<typename Q> Q read() {
21     static Q x; read(x); return x;
22 }
23 
24 const int N = 500 + 10;
25 
26 int a[N];
27 
28 int main() {
29 #ifdef DEBUG
30     freopen("in.txt", "r", stdin);
31     freopen("out.txt", "w", stdout);
32 #endif
33     
34     int T(read<int>());
35     while(T--) {
36         int n(read<int>()), cnt(0);
37         for(int i = 0; i < n; i++) {
38             read(a[i]);
39             for(int j = 0; j < i; j++) cnt ^= a[i] < a[j];
40         }
41         if((~n & 1) || !cnt) puts("possible");
42         else puts("impossible");
43     }
44     
45     return 0;
46 }
View Code

 

posted @ 2016-01-04 09:56  Showson  阅读(219)  评论(0)  编辑  收藏  举报