foo.c: In function 'main':
foo.c:9:16: warning: unused variable 'j' [-Wunused-variable]
    9 |         int i, j,num,max=0;
      |                ^
foo.c:31:36: warning: 'num' may be used uninitialized [-Wmaybe-uninitialized]
   31 |                                 num++;
      |                                 ~~~^~
foo.c:9:18: note: 'num' was declared here
    9 |         int i, j,num,max=0;
      |                  ^~~

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