{when green flag clicked} [set[pi]to(0)] [set[aaaaaaaaaaa]to(1)] |forever| |[change[pi]by(((4)/(aaaaaaaaaaa)))] ||if/(aaaaaaaaaaa)>(0)\ ||[change[aaaaaaaaaaa]by(2)] ||else| ||[change[aaaaaaaaaaa]by(-2)]| |[set[aaaaaaaaaaa]to(((0)-(aaaaaaaaaaa)))]
It eventually rounds to 3.141593
