c-gcc, 98 bytes

Result

AC

Duration

976ms

Code [DL]

y,i,j;main(x){for(scanf("%d%d",&y,&x);j=puts(""),i<y;i++)for(;j<x;)putchar(j++%~-x&&i%~-y?32:42);}

stdin

24
92

stdout

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

stderr

/tmp/code.c:1:1: warning: data definition has no type or storage class
 y,i,j;main(x){for(scanf("%d%d",&y,&x);j=puts(""),i<y;i++)for(;j<x;)putchar(j++%~-x&&i%~-y?32:42);}
 ^
/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,j;main(x){for(scanf("%d%d",&y,&x);j=puts(""),i<y;i++)for(;j<x;)putchar(j++%~-x&&i%~-y?32:42);}
   ^
/tmp/code.c:1:5: warning: type defaults to 'int' in declaration of 'j' [-Wimplicit-int]
 y,i,j;main(x){for(scanf("%d%d",&y,&x);j=puts(""),i<y;i++)for(;j<x;)putchar(j++%~-x&&i%~-y?32:42);}
     ^
/tmp/code.c:1:7: warning: return type defaults to 'int' [-Wimplicit-int]
 y,i,j;main(x){for(scanf("%d%d",&y,&x);j=puts(""),i<y;i++)for(;j<x;)putchar(j++%~-x&&i%~-y?32:42);}
       ^~~~
/tmp/code.c: In function 'main':
/tmp/code.c:1:7: warning: type of 'x' defaults to 'int' [-Wimplicit-int]
/tmp/code.c:1:19: warning: implicit declaration of function 'scanf' [-Wimplicit-function-declaration]
 y,i,j;main(x){for(scanf("%d%d",&y,&x);j=puts(""),i<y;i++)for(;j<x;)putchar(j++%~-x&&i%~-y?32:42);}
                   ^~~~~
/tmp/code.c:1:19: warning: incompatible implicit declaration of built-in function 'scanf'
/tmp/code.c:1:19: note: include '<stdio.h>' or provide a declaration of 'scanf'
+#include <stdio.h>
 y,i,j;main(x){for(scanf("%d%d",&y,&x);j=puts(""),i<y;i++)for(;j<x;)putchar(j++%~-x&&i%~-y?32:42);}
                   ^~~~~
/tmp/code.c:1:41: warning: implicit declaration of function 'puts' [-Wimplicit-function-declaration]
 y,i,j;main(x){for(scanf("%d%d",&y,&x);j=puts(""),i<y;i++)for(;j<x;)putchar(j++%~-x&&i%~-y?32:42);}
                                         ^~~~
/tmp/code.c:1:68: warning: implicit declaration of function 'putchar' [-Wimplicit-function-declaration]
 y,i,j;main(x){for(scanf("%d%d",&y,&x);j=puts(""),i<y;i++)for(;j<x;)putchar(j++%~-x&&i%~-y?32:42);}
                                                                    ^~~~~~~