DNA Consensus String

UVa1368

这道题我以为是要求一个串到所有串的距离最小，不过好像可以扩展，但是我好像写不出。

#include <stdio.h>
#include <string.h>
const int maxn = 1005;
char str[maxn][maxn], ch[5] = "ACGT", ans[maxn];
int cnt[5];
int main ( )
{
    int T, n, m, value;
    scanf ( "%d", &T );
    while ( T -- )
    {
        value = 0;
        scanf ( "%d%d", &n, &m );
        for ( int i = 0; i < n; i ++ )
            scanf ( "%s", str[i] );
        for ( int j = 0; j < m; j ++ )
        {
            memset ( cnt, 0, sizeof ( cnt ) );
            for ( int i = 0; i < n; i ++ )
            {
                for ( int k = 0; k < 4; k ++ )
                    if ( str[i][j] == ch[k] )
                        cnt[k] ++;
            }
            int mx = 0, mi = 0;
            for ( int i = 0; i < 4; i ++ )
                if ( mx < cnt[i] )  //ch存放字典序
                {
                    mx = cnt[i];
                    mi = i;
                }
            value = value+n-mx;
            ans[j] = ch[mi];
        }
        ans[m] = '\0';
        printf ( "%s\n%d\n", ans, value );
    }
    return 0;
}