If there is not a condition to end the loop, the computer will be sent through an infinite loop. Sometimes, using CTRL BREAK (QBasic 1.1) can end the infinite loop. DO...LOOP; FOR...NEXT; UNTIL (condition) _CONTINUE http://www.SchoolFreeware.com There are three types of loops for QBasic. Here in this program we that variable b as base and h as height. Sometimes, using CTRL BREAK (QBasic 1.1) can end the infinite loop.