Given an integer array of N elements, the task is to divide this array into K non-empty subsets such that the sum of elements
in every subset is same. All elements of this array should be part of exactly one partition. Examples: Input : arr = [2, 1, 4, 5, 6], K = 3 Output : Yes we can divide above array into 3 parts with equal sum as [[2, 4], [1, 5], [6]] Input : arr = [2, 1, 5, 5, 6], K = 3 Output : No It is not possible to divide above array into 3 parts with equal sum
public class Test {
boolean ans = false;
public void sqrt(int[] nums, int k) {
if (nums == null || nums.length < k || k < 0) {
System.out.println(false);
return;
}
if (k == 1) {
return;
}
int sum = 0;
for (int i : nums) {
sum += i;
}
if (sum % k != 0) {
return;
}
int ave = sum / k;
int[] visited = new int[nums.length];
Arrays.sort(nums);
dfs(nums, k, visited, 0, 0, ave);
System.out.println(ans);
}
public void dfs(int[] nums, int k, int[] visited, int pos,int sum,int ave) {
if (sum == ave) {
if (pos == k - 1) {
ans = true;
return;
}
dfs(nums, k, visited, pos + 1, 0, ave);
}
if (sum > ave) {
return;
} else {
for (int i = 0; i < nums.length; i++) {
if (nums[i] + sum > ave || ans == true) {
return;
}
if (visited[i] != 1) {
sum += nums[i];
visited[i] = 1;
dfs(nums, k, visited, pos, sum, ave);
sum -= nums[i];
visited[i] = 0;
}
}
}
}
Partition of a set into K subsets with equal sum
原文：http://www.cnblogs.com/apanda009/p/7940395.html