lintcode-线段树的修改-203

/** * Definition of SegmentTreeNode: * class SegmentTreeNode { * public: *     int start, end, max; *     SegmentTreeNode *left, *right; *     SegmentTreeNode(int start, int end, int max) { *         this->start = start; *         this->end = end; *         this->max = max; *         this->left = this->right = NULL; *     } * } */class Solution {public:        void modify(SegmentTreeNode *root, int index, int value) {        if(!root)            return ;                            if(root->start==root->end){            if(root->start==index)                root->max=value;            return ;        }                modify(root->left,index,value);        modify(root->right,index,value);                root->max=max(root->left->max,root->right->max);    }};