c-gcc, 90 bytes

Result

AC

Duration

1094ms

Code [DL]

main(w,h,i){scanf("%d%d",&h,&w);for(i=++w*h;i--;)putchar(~i%w/3&~(i/w)%h/2?32:i%w?42:10);}

stdin

47
36

stdout

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stderr

/tmp/code.c:1:1: warning: return type defaults to 'int' [-Wimplicit-int]
 main(w,h,i){scanf("%d%d",&h,&w);for(i=++w*h;i--;)putchar(~i%w/3&~(i/w)%h/2?32:i%w?42:10);}
 ^~~~
/tmp/code.c: In function 'main':
/tmp/code.c:1:1: warning: type of 'w' defaults to 'int' [-Wimplicit-int]
/tmp/code.c:1:1: warning: type of 'h' defaults to 'int' [-Wimplicit-int]
/tmp/code.c:1:1: warning: type of 'i' defaults to 'int' [-Wimplicit-int]
/tmp/code.c:1:13: warning: implicit declaration of function 'scanf' [-Wimplicit-function-declaration]
 main(w,h,i){scanf("%d%d",&h,&w);for(i=++w*h;i--;)putchar(~i%w/3&~(i/w)%h/2?32:i%w?42:10);}
             ^~~~~
/tmp/code.c:1:13: warning: incompatible implicit declaration of built-in function 'scanf'
/tmp/code.c:1:13: note: include '<stdio.h>' or provide a declaration of 'scanf'
+#include <stdio.h>
 main(w,h,i){scanf("%d%d",&h,&w);for(i=++w*h;i--;)putchar(~i%w/3&~(i/w)%h/2?32:i%w?42:10);}
             ^~~~~
/tmp/code.c:1:50: warning: implicit declaration of function 'putchar' [-Wimplicit-function-declaration]
 main(w,h,i){scanf("%d%d",&h,&w);for(i=++w*h;i--;)putchar(~i%w/3&~(i/w)%h/2?32:i%w?42:10);}
                                                  ^~~~~~~