script.js

let inputBox = document.getElementById('inputBox')
let buttons = document.querySelectorAll('button')

let string= ''

buttons.forEach(element=>{

    element.addEventListener('click', (b) =>{

        if(b.target.innerText=='='){
            string=String(eval(string))
            inputBox.value=string;
        }


        else if(b.target.innerText== 'AC'){
            string = ''
            inputBox.value = string;
        }


        else if(b.target.innerText== 'DEL'){
            string = string.substring(0,string.length-1)
            inputBox.value = string;
            
        }

        else if(b.target.id =='plusMinus'){
            string = String(-eval(string))
            inputBox.value = string;
        }



        else{
            string += b.target.innerText
            inputBox.value = string;
        }

    })
})