bash-busybox, 73 bytes

Result

AC

Duration

1556ms

Code [DL]

read h
read w
for((;;)){
printf \\$[++i%w/2*c?40:i>w?c=h--%h,i=0,12:52]
}

stdin

83
72

stdout

************************************************************************
*                                                                      *
*                                                                      *
*                                                                      *
*                                                                      *
*                                                                      *
*                                                                      *
*                                                                      *
*                                                                      *
*                                                                      *
*                                                                      *
*                                                                      *
*                                                                      *
*                                                                      *
*                                                                      *
*                                                                      *
*                                                                      *
*                                                                      *
*                                                                      *
*                                                                      *
*                                                                      *
*                                                                      *
*                                                                      *
*                                                                      *
*                                                                      *
*                                                                      *
*                                                                      *
*                                                                      *
*                                                                      *
*                                                                      *
*                                                                      *
*                                                                      *
*                                                                      *
*                                                                      *
*                                                                      *
*                                                                      *
*                                                                      *
*                                                                      *
*                                                                      *
*                                                                      *
*                                                                      *
*                                                                      *
*                                                                      *
*                                                                      *
*                                                                      *
*                                                                      *
*                                                                      *
*                                                                      *
*                                                                      *
*                                                                      *
*                                                                      *
*                                                                      *
*                                                                      *
*                                                                      *
*                                                                      *
*                                                                      *
*                                                                      *
*                                                                      *
*                                                                      *
*                                                                      *
*                                                                      *
*                                                                      *
*                                                                      *
*                                                                      *
*                                                                      *
*                                                                      *
*                                                                      *
*                                                                      *
*                                                                      *
*                                                                      *
*                                                                      *
*                                                                      *
*                                                                      *
*                                                                      *
*                                                                      *
*                                                                      *
*                                                                      *
*                                                                      *
*                                                                      *
*                                                                      *
*                                                                      *
*                                                                      *
************************************************************************

stderr

/code.bash: line 4: ++i%w/2*c?40:i>w?c=h--%h,i=0,12:52: division by 0 (error token is "h,i=0,12:52")