foo.c: In function 'main':
foo.c:21:2: warning: implicit declaration of function 'scanf' [-Wimplicit-function-declaration]
   21 |  scanf("%d %d",&n1,&n2);
      |  ^~~~~
foo.c:21:2: warning: incompatible implicit declaration of built-in function 'scanf'
foo.c:1:1: note: include '<stdio.h>' or provide a declaration of 'scanf'
  +++ |+#include <stdio.h>
    1 | int FindiSecondMax(int c[],int n)
foo.c:28:2: warning: implicit declaration of function 'printf' [-Wimplicit-function-declaration]
   28 |  printf("%d ",drd1);
      |  ^~~~~~
foo.c:28:2: warning: incompatible implicit declaration of built-in function 'printf'
foo.c:28:2: note: include '<stdio.h>' or provide a declaration of 'printf'
foo.c: In function 'FindiSecondMax':
foo.c:16:9: warning: 'drd' may be used uninitialized in this function [-Wmaybe-uninitialized]
   16 |  return drd;
      |         ^~~
foo.c:13:14: warning: 't' may be used uninitialized in this function [-Wmaybe-uninitialized]
   13 |   if(max<c[i]&&i!=t)
      |      ~~~~~~~~^~~~~~

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