script.js

const calculatorscreen=document.querySelector('.calculator-screen');

const updatescreen=(number)=>{
	calculatorscreen.value=number;
}



const numbers=document.querySelectorAll(".number");

numbers.forEach((number)=>{
	number.addEventListener("click",(event)=>{
		inputNumber(event.target.value);
		updatescreen(currentInput);
	})
})



let prevInput='0';
let calculationOperator='';
let currentInput='0';

const inputNumber=(number)=>{
	if(currentInput==='0')
	{
		currentInput=number;
	}
	else
	{
		currentInput+=number;
	}
}


const operators=document.querySelectorAll(".operator");

operators.forEach((operator)=>{
	operator.addEventListener("click",(event)=>{
		inputoperator(event.target.value);
	})
})

const inputoperator=(operator)=>{
	prevInput=currentInput;
	calculationOperator=operator;
	currentInput='0';
}

const equalSign=document.querySelector('.equal-sign');

equalSign.addEventListener("click",()=>{
	calculate();
	updatescreen(currentInput);
})

const calculate=()=>{
	let result=0;
	switch(calculationOperator){
		case '+':
			result=parseInt(prevInput)+parseInt(currentInput);
			break;
		case '-':
			result=parseInt(prevInput)-parseInt(currentInput);
			break;
		case '*':
			result=parseInt(prevInput)*parseInt(currentInput);
			break;
		case '/':
			result=parseInt(prevInput)/parseInt(currentInput);
			break;
		default:
			return;
	}
currentInput=result.toString();
calculationOperator='';
}



const clearBtn=document.querySelector('.all-clear');

clearBtn.addEventListener("click",()=>{
	clearAll();
	updatescreen(currentInput);
})

const clearAll=()=>{
	prevInput='0';
	calculationOperator='';
	currentInput='0';
}