一个整数组，长度为 n，将其分为 m 份，使各的和相等求 m 的最大值，比如{3,2,4,3,6} 可以分成{3,2,4,3,6,} m=1;{3,6}{2,4,3}m=2 {3,3}{2,4}{6} m=3 所以m的最大值是3

package number;

/**
 * @author ycsun E-mail:stevesun521@gmail.com
 * @version 创建时间：2012-10-3 下午2:59:49 类说明
 */
public class ArrayOperation {
    private int[] arr;
    private int[] aux;
    private int groupid = 0;

    public ArrayOperation(int[] arr) {
        this.arr = arr;
        aux = new int[arr.length];
    }

    /**
     * @param int[] arr 一个整数组，长度为 n，将其分为 m 份，使各的和相等求 m 的最大值，比如{3,2,4,3,6}
     *        可以分成{3,2,4,3,6,} m=1;{3,6}{2,4,3}m=2 {3,3}{2,4}{6} m=3 所以m的最大值是3
     */
    public int averageSplitArray() {
        if (arr.length == 1) {
            return 1;
        }
        int res = 1;
        int sum = 0;
        for (int i = 0; i < arr.length; i++)
            sum += arr[i];
        for (int i = 1; i < arr.length; i++) {
            if (sum % i != 0)
                continue;
            groupid = 0;
            for (int j = 0; j < arr.length; j++)
                aux[j] = 0;
            averageSplitArray(i,sum / i,sum/i);
            int gnum = i;
            if (gnum > 0) {
                System.out.println("gnum :" + gnum);
                for (int g = 1; g <= i; g++) {
                    System.out.print("{");
                    for (int k = 0; k < aux.length; k++) {
                        if (aux[k] == g) {
                            System.out.print(arr[k] + ",");
                        }
                    }
                    System.out.println("}");
                }
            }
        }
        return res;
    }

    private boolean  averageSplitArray(int groupnum,int groupsum,int goalsum) {
        if (goalsum == 0) {
            groupid++;
            goalsum=groupsum;
            if (groupid == groupnum + 1)
                return true;
        }
        for (int i = 0; i < aux.length; i++) {
            if (aux[i] != 0)
                continue;
            aux[i] = groupid;
            if(averageSplitArray(groupnum,groupsum,goalsum-arr[i])) return true;
            aux[i]=0;
        }
        return false;
    }

    public static void main(String[] args) {
        int[] arr = { 3, 2, 4, 3, 6 };
        ArrayOperation ao = new ArrayOperation(arr);
        ao.averageSplitArray();
    }

}