Educational Codeforces Round 56 Div. 2 翻车记

　　A：签到。

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　　B：仅当只有一种字符时无法构成非回文串。

#include<iostream> 
#include<cstdio>
#include<cmath>
#include<cstdlib>
#include<cstring>
#include<algorithm>
using namespace std;
#define ll long long
#define N 1010
char getc(){char c=getchar();while ((c<'A'||c>'Z')&&(c<'a'||c>'z')&&(c<'0'||c>'9')) c=getchar();return c;}
int gcd(int n,int m){return m==0?n:gcd(m,n%m);}
int read()
{
    int x=0,f=1;char c=getchar();
    while (c<'0'||c>'9') {if (c=='-') f=-1;c=getchar();}
    while (c>='0'&&c<='9') x=(x<<1)+(x<<3)+(c^48),c=getchar();
    return x*f;
}
int T,n,cnt[26];
char s[N];
int main()
{
/*#ifndef ONLINE_JUDGE
    freopen("a.in","r",stdin);
    freopen("a.out","w",stdout);
#endif*/
    T=read();
    while (T--)
    {
        scanf("%s",s+1);n=strlen(s+1);
        memset(cnt,0,sizeof(cnt));
        for (int i=1;i<=n;i++) cnt[s[i]-'a']++;
        int tot=0;
        for (int i=0;i<26;i++) if (cnt[i]) tot++;
        if (tot==1) cout<<-1<<endl;
        else
        {
            for (int i=0;i<26;i++)
                for (int j=1;j<=cnt[i];j++)
                putchar(i+'a');
            cout<<endl;
        }
    }
    return 0;
}

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