SOURCE

var i=1;
var count=0;
while(i<=100){
    count+=i;
    i++;
}
document.write(count+'<br\>');

var m=1;
var count1=0;
do{
    count1+=m;
    m++;
}while(m<=100);
document.write(count1+'<br\>');

var sum=0;
for(var i=1;i<=100;i++){
    sum+=i;
}
document.write(sum)