foo.c: In function 'FullPermutation':
foo.c:11:8: warning: unused variable 'x' [-Wunused-variable]
   11 |  int i,x=0,k,j=0,u[100001],y=0;
      |        ^
foo.c: In function 'main':
foo.c:60:28: warning: unused variable 'k' [-Wunused-variable]
   60 |  int m,n,i=0,t,b,num,sum=0,k,a[100001];
      |                            ^
foo.c:60:16: warning: unused variable 'b' [-Wunused-variable]
   60 |  int m,n,i=0,t,b,num,sum=0,k,a[100001];
      |                ^
foo.c:60:14: warning: unused variable 't' [-Wunused-variable]
   60 |  int m,n,i=0,t,b,num,sum=0,k,a[100001];
      |              ^
foo.c: In function 'FullPermutation':
foo.c:12:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   12 |  scanf("%d",&k);
      |  ^~~~~~~~~~~~~~
foo.c: In function 'main':
foo.c:61:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   61 |  scanf("%d",&m);
      |  ^~~~~~~~~~~~~~
foo.c:68:3: warning: 'num' may be used uninitialized in this function [-Wmaybe-uninitialized]
   68 |   FullPermutation(a, a[0],a[num-1],num,sum);
      |   ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

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