foo.cc: In function 'int main()':
foo.cc:9:24: warning: unused variable 'k' [-Wunused-variable]
    9 |  long long int n,m,i,j,k,ans=0,x,y,p=0,q=0;
      |                        ^
foo.cc:9:36: warning: unused variable 'p' [-Wunused-variable]
    9 |  long long int n,m,i,j,k,ans=0,x,y,p=0,q=0;
      |                                    ^
foo.cc:9:40: warning: unused variable 'q' [-Wunused-variable]
    9 |  long long int n,m,i,j,k,ans=0,x,y,p=0,q=0;
      |                                        ^
foo.cc:10:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   10 |  scanf("%lld %lld",&n,&m);
      |  ~~~~~^~~~~~~~~~~~~~~~~~~
foo.cc:13:23: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   13 |  for(i=0;i<n;i++)scanf("%lld",&a[i]);
      |                  ~~~~~^~~~~~~~~~~~~~
foo.cc:15:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   15 |   scanf("%lld",&b[i]);
      |   ~~~~~^~~~~~~~~~~~~~

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