c-gcc, 87 bytes

Result

AC

Duration

1083ms

Code [DL]

y,i;main(x){for(scanf("%d%d",&y,&x),x++;i<y*x;)putchar(i++%x?i%x>2&&i/x%~-y?32:42:10);}

stdin

35
54

stdout

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stderr

/tmp/code.c:1:1: warning: data definition has no type or storage class
 y,i;main(x){for(scanf("%d%d",&y,&x),x++;i<y*x;)putchar(i++%x?i%x>2&&i/x%~-y?32:42:10);}
 ^
/tmp/code.c:1:1: warning: type defaults to 'int' in declaration of 'y' [-Wimplicit-int]
/tmp/code.c:1:3: warning: type defaults to 'int' in declaration of 'i' [-Wimplicit-int]
 y,i;main(x){for(scanf("%d%d",&y,&x),x++;i<y*x;)putchar(i++%x?i%x>2&&i/x%~-y?32:42:10);}
   ^
/tmp/code.c:1:5: warning: return type defaults to 'int' [-Wimplicit-int]
 y,i;main(x){for(scanf("%d%d",&y,&x),x++;i<y*x;)putchar(i++%x?i%x>2&&i/x%~-y?32:42:10);}
     ^~~~
/tmp/code.c: In function 'main':
/tmp/code.c:1:5: warning: type of 'x' defaults to 'int' [-Wimplicit-int]
/tmp/code.c:1:17: warning: implicit declaration of function 'scanf' [-Wimplicit-function-declaration]
 y,i;main(x){for(scanf("%d%d",&y,&x),x++;i<y*x;)putchar(i++%x?i%x>2&&i/x%~-y?32:42:10);}
                 ^~~~~
/tmp/code.c:1:17: warning: incompatible implicit declaration of built-in function 'scanf'
/tmp/code.c:1:17: note: include '<stdio.h>' or provide a declaration of 'scanf'
+#include <stdio.h>
 y,i;main(x){for(scanf("%d%d",&y,&x),x++;i<y*x;)putchar(i++%x?i%x>2&&i/x%~-y?32:42:10);}
                 ^~~~~
/tmp/code.c:1:48: warning: implicit declaration of function 'putchar' [-Wimplicit-function-declaration]
 y,i;main(x){for(scanf("%d%d",&y,&x),x++;i<y*x;)putchar(i++%x?i%x>2&&i/x%~-y?32:42:10);}
                                                ^~~~~~~