CODECHEF Minimum Good Permutation

题目链接：https://www.codechef.com/SEPT17/problems/MINPERM
求最小的错排
奇偶要分类讨论
偶数个时把[1,n]两两分组，每组两个交换，如[1,2]，[3,4]等
偶数个时前面一样，后面三个特殊处理，n−2,n−1,n变成n−1,n,n−2
贴代码

#include<cstdio>#include<cstring>using namespace std;int n,m,Q;int main(){//  freopen("2.in","r",stdin);//  freopen("2.out","w",stdout);    scanf("%d",&Q);    while (Q--){        scanf("%d",&n);        m=n%2==0?n:n-3;        for (int i=1;i<=m;i++)i%2==0?printf("%d ",i-1):printf("%d ",i+1);        if (n%2==1)printf("%d %d %d ",n-1,n,n-2);        printf("\n");    }    return 0;} 

【写的有漏洞的，欢迎路过大神吐槽】
2017/09/11 19:27:13
Ending.