var a = prompt("Enter s for squareEnter t for triangle")
if (a=="s", a=="S"){
var side = prompt("enter the value")
var b = side *side;
console.log(b,"this is square area")
}
else if(a=="t", a=="T"){
var base = prompt("enter the base value")
// base = 1/2;
var height = prompt("enter the height")
area=1/2*base*height;
console.log(area,"this is the area of triangle")
}
else{console.log("invalid input")};