JavaScript for迴圈語句的特殊案例，用代碼解決數學中的問題

案例一:

var num = 100;
var people = 100;
var big,small;
         for(big=0;big<=33;big++){
            small=people-big;
            if(big*3+small/3==num){
                document.write("大和尚為:"+big+" 人  小和尚為:"+small+"人");
            }
 }

案例二：

 var money = 100;
 var num = 100;
 var man,wuman,child;
        for(man=0;man<=20;man++){
            for(wuman =0;wuman<=33;wuman++){
                child = num -man - wuman
                if(5*man+3*wuman+child/3==money){
                document.write('公雞數量為'+man,'母雞'+wuman,'小雞'+child)
                document.write('<br>')
            }
            }
         }

for(var a= 15;a<=100;a+=15){
            for(var b=2;b<=100;b+=2){
                for(var c=5;c<=100;c+=5){
                    if(a+b+c ==100){
                        document.write('洗髮水'+ a/15+'香皂'+b/2+'牙刷'+c/5);
                        document.write('<br>')
                    }
                }
            }
        }

var age = 3;
        for(var i=1 ;i<5;i++){
            age+=2
            document.write('第'+(5-i)+'個小朋友'+age+'歲')
            document.write('<br>')
 }

案例五：

for(var a = 1;a<=20;a+=1){
            for(var b = 2;b<=20;b+=2){
                for(var c=5;c<=20;c+=5){
                    if(a+b+c==20){
                        document.write('1需要：'+ a/1+'b需要：'+b/2+'c需要：'+c/5);
                         document.write('<br>')
                    }
                }
            }
        }