function equal() {
    return prompt("Enter the passcode");
}

function number(input, passcode){
    if(input == value) {
        alert("Welcome");
    } else if(input != value) {
        alert("Wrong Passcode");
    }
}

// Passcode
var value = "1489";
// User Input
input1 = equal();
// Check if user input is correct
number(input1, value);