var myHeight; var myWeight; var bmi; myHeight = prompt("请输入您的身高:"); myWeight = prompt("请输入您的体重:"); bmi = myWeight/((myHeight)^2); // alert(bmi); if(bmi>25){ alert("刘翔超级无敌胖,你该减减肥,多给你女朋友吃点"); }else if(bmi<20){ alert("瘦,你该多吃米饭,少吃汉堡,将汉堡给你女朋友吃"); }else{ alert("正常,你该多做饭给你女朋友吃"); }