Satya's blog - A C question

From http://www.livejournal.com/users/bluesmoon/21517.html.

int i, n = 20;
for(i = 0; i < n; i--)
printf("-");

You've got to get it to print - 20 times. You may add, subtract OR replace only one character in the above code.
There are 3 solutions.
Ercynpr gur v qrperzrag jvgu a qrperzrag
Chg n zvahf fvta orsber gur v va gur pbzcnevfba
Punatr gur yrffguna fvta gb n cyhf fvta