Sword Point offer problem sets 1

1. Print binary tree

The program is very simple, but it made a small mistake, dead and alive can not find, write code to pay attention to AH

Here the subtree, to note is node->left, the result is written root->left

vector<int> Printfromtoptobottom (TreeNode *root) {Vector<int>Res; if(NULL = =root)returnRes; TreeNode*node; Deque<TreeNode*>tmp;    Tmp.push_back (root);  while(Tmp.size ()) {node=Tmp.front (); Res.push_back (Node-val);        Tmp.pop_front (); if(node->Left ) tmp.push_back (node-Left ); if(node->Right ) tmp.push_back (node-Right ); }    returnRes;}

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2. Seeking 1+2+...+n

classa{ Public: A () {++n;sum+=N; }      Static intgetsum () {returnsum; }    Static voidReset () {n=0; sum=0; }    ~A () {}Private:            Static intN; Static intsum;}; inta::n=0;inta::sum=0; classSolution { Public:         intSum_solution (intN) {a::reset ();//necessary, the test assembly repeats its operationA* tmp=NewA[n]; Delete[] tmp; returna::getsum (); }};

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3. Two Tree image

classSolution { Public:    voidMirror (TreeNode *proot) {                if(null==proot| | (null==proot->left&&null==proot->Right )) return;    Mirrorset (Proot); }        voidMirrorset (treenode*root) {                if(null==root| | (null==root->left&&null==root->Right )) return; TreeNode*tmp=root->Left ; Root->left=root->Right ; Root->right=tmp; if(root->Left ) mirrorset (Root-Left ); if(root->Right ) mirrorset (Root-Right ); }};

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Sword Point offer problem sets 1