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Create 106-Construct-Binary-Tree-from-Inorder-and-Postorder-Traversal.java

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	`1`	`+//This video helped https://www.youtube.com/watch?v=LgLRTaEMRVc&ab_channel=takeUforward`
	`2`	`+`
	`3`	`+classSolution {`
	`4`	`+publicTreeNodebuildTree(int[]inorder,int[]postorder) {`
	`5`	`+HashMap<Integer,Integer>inMap =newHashMap<>();`
	`6`	`+for (inti =0;i<inorder.length;i++) {`
	`7`	`+inMap.put(inorder[i],i);`
	`8`	`+ }`
	`9`	`+returnhelper(inorder,0,inorder.length-1,postorder,0,postorder.length-1,inMap);`
	`10`	`+ }`
	`11`	`+`
	`12`	`+publicTreeNodehelper(int[]inorder,intiStart,intiEnd,int[]postorder,intpStart,intpEnd,HashMap<Integer,Integer>inMap) {`
	`13`	`+if (pStart>pEnd \|\|iStart>iEnd) {`
	`14`	`+returnnull;`
	`15`	`+ }`
	`16`	`+TreeNoderoot =newTreeNode(postorder[pEnd]);`
	`17`	`+intindex =inMap.get(postorder[pEnd]);`
	`18`	`+intnumsLeft =index-iStart;`
	`19`	`+root.left =helper(inorder,iStart,index-1,postorder,pStart,pStart+numsLeft-1,inMap);`
	`20`	`+root.right =helper(inorder,index+1,iEnd,postorder,pStart+numsLeft,pEnd-1,inMap);`
	`21`	`+returnroot;`
	`22`	`+ }`
	`23`	`+`
	`24`	`+}`

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