JSFiddle - React, Tailwind, and code Playground

by grantk

JavaScript

var a1, a2, b1, b2, c1, c2;
a1 = [4,9,3,7,8];
a2 = [3,7];

b1 = [1,3,5];
b2 = [1];

c1 = [7,8,9];
c2 = [8,9,10];

alert(findArray(a1,a2));
alert(findArray(b1,b2));
alert(findArray(c1,c2));

function findArray(a1, a2){
	for(var i=0; i<a1.length; i++){
		if(a2[0] === a1[i]){
			//first entry found
			for(var j=1; j<a2.length; j++){
				if(a2[j] !== a1[i +j]){
					return -1;
				}
			}
			return i;
		}
	}
	return -1;
}