pair<int,int> robHelper(TreeNode* root) {
if(root==NULL) {
return make_pair(0,0);
}
pair<int,int> left = robHelper(root->left);
pair<int,int> right = robHelper(root->right);
int first = left.second+right.second+root->val;
int second = max(left.first, left.second) + max(right.first, right.second);
return make_pair(first, second);
}
int rob(vector<int>& nums) {
if (nums.size() == 0) {
return 0;
}
if (nums.size() == 1) {
return nums[0];
}
return max(robHelper(nums, 0, nums.size() - 1), // [first, last)
robHelper(nums, 1, nums.size())); // [second, last + 1)
}
int robHelper(int* nums, int numsSize,int start){
if(nums==NULL||numsSize<1||numsSize<=start){
return 0;
}
if(result[start]!=-1){
return result[start];
}
int res1=robHelper(nums,numsSize,start+2);
int res2=robHelper(nums,numsSize,start+3);
int res=nums[start]+max(res1,res2)
result[start]=res;
return ;
}
int rob(int* nums, int numsSize) {
if(nums==NULL||numsSize<1){
return 0;
}
result=(int *)malloc(numsSize*sizeof(int));
if(result==NULL){
exit(EXIT_FAILURE);
}
memset(result,-1,numsSize*sizeof(int));//初始化为-1
int fristElementMax=robHelper(nums,numsSize,0);//第一个元素被盗后产生的最大值
int secondElementMax=robHelper(nums,numsSize,1);//第二个元素被盗后可能产生的最大值
return fristElementMax>secondElementMax?fristElementMax:secondElementMax;
}
vector<int> robHelper(TreeNode* root) {
if(root == NULL) {
return vector<int>(2,0);
}
vector<int> left = robHelper(root->left);
vector<int> right = robHelper(root->right);
vector<int> res;
// res[0] : pick up root
res.push_back(left[1] + right[1] + root->val);
// res[1] : no root obviously
res.push_back(max(left[0],left[1]) + max(right[0],right[1]));
return res;
}
int rob(TreeNode* root) {
pair<int,int> p=robHelper(root);
return max(p.first,p.second);
}
int rob(TreeNode* root) {
vector<int> dp = robHelper(root);
return max(dp[0], dp[1]);
}
int rob(vector<int>& nums) {
if(nums.size() == 0) return 0;
if(nums.size() == 1) return nums[0];
int n = nums.size();
return max(robHelper(nums,0,n-2),robHelper(nums,1,n-1));
}