UVA 11100(p81)----The Trip, 2007

#include<bits/stdc++.h>#define debuusing namespace std;const int maxn=1e4+50;int ans,n;int a[maxn];map<int,int> m;void solve(){    sort(a,a+n);    printf("%d\n",ans);    for(int i=0; i<ans; i++)    {        printf("%d",a[i]);        for(int j=i+ans; j<n; j+=ans)            printf(" %d",a[j]);        printf("\n");    }}int main(){#ifdef debug    freopen("in.in","r",stdin);#endif // debug    while(scanf("%d",&n)==1&&n)    {        ans=0;m.clear();        for(int i=0; i<n; i++)        {            scanf("%d",&a[i]);            if(!m[a[i]]) m[a[i]]=1;            else m[a[i]]++;            ans=max(ans,m[a[i]]);        }        solve();    }    return 0;}

题目地址：https://uva.onlinejudge.org/index.php?option=com_onlinejudge&Itemid=8&page=show_problem&problem=2041

题解：ans=max（每个数字出现次数），输出则按照ans等差输出。