// global scope
var a = 1;
function one() {
  // alerts ‘1’
  document.writeln("Inside one() ->"+a+"<br>");
}
one();
// global scope
var b = 1;
function two(b) {
    // functional scope
    //alerts the given argument, not the global value of 1
    document.writeln("Inside two() ->"+b+"<br>")
}
two(2);
// functional scope again
function three() {
    var a = 3;
  // alerts ‘3’
  document.writeln("Inside three() ->"+a+"<br>");
}
three(); // Uncomment this to check functional scope

var i,j;
// i IS NOT known here
// j IS NOT known here
document.writeln("Before loop()-"+"i="+i+" j="+j+"<br>");
function loop(arr) {
    // i IS NOT known here
    // j IS NOT known here
    document.writeln("inside loop() before loops-"+"i="+i+" j="+j+"<br>");
    for( var i = 0; i < arr.length; i++ ) {
      // i IS known here
      // j IS NOT known here
       document.writeln("inside i loop-"+"i="+i+" j="+j+"<br>");
    };
    // i IS known here
    // j IS NOT known here
    for( let j = 0; j < arr.length; j++ ) {
      // i IS known here
      // j IS known here
      document.writeln("inside j loop-"+"i="+i+" j="+j+"<br>");
    };
    // i IS known here
    // j IS NOT known here
    document.writeln("inside loop() after loops-"+"i="+i+" j="+j+"<br>");
}
// i IS NOT known here
// j IS NOT known here
loop([1]); // Uncomment this to check block scope
document.writeln("after loop()-"+"i="+i+" j="+j+"<br>");