Ugly Pairs

https://codeforces.com/contest/1156/problem/B

题解：贪心

/*
*@Author:   STZG
*@Language: C++
*/
#include <bits/stdc++.h>
#include<iostream>
#include<algorithm>
#include<cstdlib>
#include<cstring>
#include<cstdio>
#include<string>
#include<vector>
#include<bitset>
#include<queue>
#include<deque>
#include<stack>
#include<cmath>
#include<list>
#include<map>
#include<set>
//#define DEBUG
#define RI register int
#define endl "\n"
using namespace std;
typedef long long ll;
//typedef __int128 lll;
const int N=100000+10;
const int M=100000+10;
const int MOD=1e9+7;
const double PI = acos(-1.0);
const double EXP = 1E-8;
const int INF = 0x3f3f3f3f;
int t,n,m,k,p,l,r,u,v;
int ans,cnt,flag,temp,sum;
int a[30];
char str[N];
struct node{};
int main()
{
#ifdef DEBUG
	freopen("input.in", "r", stdin);
	//freopen("output.out", "w", stdout);
#endif
    //ios::sync_with_stdio(false);
    //cin.tie(0);
    //cout.tie(0);
    scanf("%d",&t);
    while(t--){
    //scanf("%d",&n);
        cin>>str;
        int len=strlen(str);
        memset(a,0,sizeof(a));
        for(int i=0;i<len;i++){
            a[str[i]-'a']++;
        }
        string ans1="",ans2="",ans="";
        cnt=0;
        for(int i=0;i<26;i+=2){
            while(a[i]){
                ans1+=(i+'a');
                a[i]--;
                cnt++;
            }
        }
        for(int i=1;i<26;i+=2){
            while(a[i]){
                ans2+=(i+'a');
                a[i]--;
                //cnt++;
            }
        }
        if(ans1.size()>0&&ans2.size()>0){
            if(abs(ans1[cnt-1]-ans2[0])!=1){
                ans=ans1+ans2;
            }else{
                ans=ans2+ans1;
            }
        }else{
            if(ans1.size()>0){
                ans=ans1;
            }else{
                ans=ans2;
            }
        }

        flag=1;
        for(int i=1;i<len;i++){
            if(abs(ans[i-1]-ans[i])==1){
                flag=0;
                break;
            }
        }
        cout<<(flag?ans:"No answer")<<endl;
    }

#ifdef DEBUG
	printf("Time cost : %lf s\n",(double)clock()/CLOCKS_PER_SEC);
#endif
    //cout << "Hello world!" << endl;
    return 0;
}