D. Similar Arrays
time limit per test
1 second
memory limit per test
512 megabytes
input
standard input
output
standard output
Vasya had an array of nn integers, each element of the array was from 11 to nn . He chose mm pairs of different positions and wrote them down to a sheet of paper. Then Vasya compared the elements at these positions, and wrote down the results of the comparisons to another sheet of paper. For each pair he wrote either "greater", "less", or "equal".
After several years, he has found the first sheet of paper, but he couldn't find the second one. Also he doesn't remember the array he had. In particular, he doesn't remember if the array had equal elements. He has told this sad story to his informatics teacher Dr Helen.
She told him that it could be the case that even if Vasya finds his second sheet, he would still not be able to find out whether the array had two equal elements.
Now Vasya wants to find two arrays of integers, each of length nn . All elements of the first array must be distinct, and there must be two equal elements in the second array. For each pair of positions Vasya wrote at the first sheet of paper, the result of the comparison must be the same for the corresponding elements of the first array, and the corresponding elements of the second array.
Help Vasya find two such arrays of length nn , or find out that there are no such arrays for his sets of pairs.
Input
The first line of input contains two integers nn , mm — the number of elements in the array and number of comparisons made by Vasya (1≤n≤1000001≤n≤100000 , 0≤m≤1000000≤m≤100000 ).
Each of the following mm lines contains two integers aiai , bibi — the positions of the ii -th comparison (1≤ai,bi≤n1≤ai,bi≤n ; ai≠biai≠bi ). It's guaranteed that any unordered pair is given in the input at most once.
Output
The first line of output must contain "YES" if there exist two arrays, such that the results of comparisons would be the same, and all numbers in the first one are distinct, and the second one contains two equal numbers. Otherwise it must contain "NO".
If the arrays exist, the second line must contain the array of distinct integers, the third line must contain the array, that contains at least one pair of equal elements. Elements of the arrays must be integers from 11 to nn .
Examples
Input
1 0
Output
NO
Input
3 1 1 2
Output
YES 1 3 2 1 3 1
Input
4 3 1 2 1 3 2 4
Output
YES 1 3 4 2 1 3 4 1
题意：让你构造你两个长度为n的数组a,b，有m对比较组合，a数组需要每一个每个数都小于n且每个数只出现一次，b数组需要这m对组合的大小关系和第一个相同。
思路：做的时候，认为两个位置有比较对的时候还可以微调可以满足规则，没有的话更可以，写了好久理所当然的WA了，最后打完了，想了好久，想过用度从小到大的赋值为1，2...n，或者最大的那个为1，其他的从2 开始赋值，最后成功的WA了，看了了好多份别人的代码，才知道需要找一个没有比较对的让a[i]=1,a[j]=2,b[i]=1,b[j]=1,其他的从3开始依次赋值就好了，刚看到的时候想不明白为什么，后来仔细想来想，发现也挺有道理的，这两个没有大小的比较，让a为1，2，b为1，1，和其他的都是大于3的一定会比1，2大，大小一定全都会满足，完美！，，但是这个我真特么的想不到啊！！
代码：
#include<stdio.h>
#include<string.h>
#include<cmath>
#include<stdlib.h>
#include<time.h>
#include<algorithm>
#include<iostream>
#include<vector>
#include<queue>
#include<iterator>
#include<set>
#include<map>
#include<bitset>
#define ll long long
#define qq printf("QAQ\n");
using namespace std;
const int maxn=2e5+5;
const int inf=0x3f3f3f3f;
const ll linf=0x3f3f3f3f3f3f3f3f;
const int mod=1e9+7;
const double e=exp(1.0);
const double pi=acos(-1);
const double eps=1e-6;
set<int>s[maxn];
int a[maxn],b[maxn];
int main()
{
int n,m,l,r;
while(scanf("%d%d",&n,&m)!=EOF)
{
for(int i=1;i<=m;i++)
{
scanf("%d%d",&l,&r);
if(l>r)swap(l,r);
s[l].insert(r);
}
int f=0;
for(int i=1;i<=n;i++)
{
for(int j=i+1;j<=n;j++)
{
if(!s[i].count(j)){
//puts("YES");
f=1;
a[i]=1;a[j]=2;
b[i]=1;b[j]=1;
int now=3;
for(int k=n;k>=1;k--)
if(k!=i&&j!=k)a[k]=now,b[k]=now++;
puts("YES");
for(int i=1;i<=n;i++)
printf("%d%c",a[i],i==n?'\n':' ');
for(int i=1;i<=n;i++)
printf("%d%c",b[i],i==n?'\n':' ');
return 0;
}
}
}
puts("NO");
}
return 0;
}