/in/foo.c: In function 'main':
/in/foo.c:5:14: warning: missing braces around initializer [-Wmissing-braces]
  int a[2][3]={1,2,3,4,5,6};
              ^
/in/foo.c:5:14: note: (near initialization for 'a')
/in/foo.c:10:9: warning: too many arguments for format [-Wformat-extra-args]
  printf("\n",a);
         ^~~~
/in/foo.c:8:16: warning: iteration 2 invokes undefined behavior [-Waggressive-loop-optimizations]
  { a[i][j]=a[j][i];
            ~~~~^~~
/in/foo.c:7:4: note: within this loop
  { for(int j=0;j<3;j++)
    ^~~
/in/foo.c:8:13: warning: array subscript is above array bounds [-Warray-bounds]
  { a[i][j]=a[j][i];
            ~^~~
/in/foo.c:8:13: warning: array subscript is above array bounds [-Warray-bounds]