foo.c: In function 'main':
foo.c:9:20: warning: unused variable 'i' [-Wunused-variable]
  int a[N],b[N],n,m,i,p,q,u,v;
                    ^
foo.c:10:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d%d",&n,&m);
  ^~~~~~~~~~~~~~~~~~~
foo.c: In function 'Input':
foo.c:25:3: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d",&a[i]);
   ^~~~~~~~~~~~~~~~~
foo.c:26:1: warning: control reaches end of non-void function [-Wreturn-type]
 }
 ^
foo.c: In function 'main':
foo.c:53:5: warning: 'max2' may be used uninitialized in this function [-Wmaybe-uninitialized]
   if(a[i]==x)
     ^
foo.c:30:15: note: 'max2' was declared here
     int max1, max2, i;
               ^~~~
foo.c:53:5: warning: 'max2' may be used uninitialized in this function [-Wmaybe-uninitialized]
   if(a[i]==x)
     ^
foo.c:30:15: note: 'max2' was declared here
     int max1, max2, i;
               ^~~~
foo.c: In function 'FindiSecondMax':
foo.c:47:12: warning: 'max2' may be used uninitialized in this function [-Wmaybe-uninitialized]
     return max2;
            ^~~~

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