is bst check

by amrendra kumar

JavaScript

const isBst = (array) => {
	let root = Number.MIN_VALUE;
  
  let stack = [];
  
  for (let i = 0; i < array.length; i++) {
  	if(array[i] < root) {
    	return false;
    }
    
    while(stack.length && stack[stack.length-1] < array[i]) {
    	root = stack[0];
      stack.shift(stack[0])
    }
    
    stack.unshift(array[i]);
  }
  return true; 
}


console.log(isBst([2,1,5,4,6]))