foo.cc: In function 'int main()':
foo.cc:10:17: warning: unused variable 'b' [-Wunused-variable]
     long long a,b,c,d,e,f,g,n,i,j;
                 ^
foo.cc:10:19: warning: unused variable 'c' [-Wunused-variable]
     long long a,b,c,d,e,f,g,n,i,j;
                   ^
foo.cc:10:21: warning: unused variable 'd' [-Wunused-variable]
     long long a,b,c,d,e,f,g,n,i,j;
                     ^
foo.cc:10:23: warning: unused variable 'e' [-Wunused-variable]
     long long a,b,c,d,e,f,g,n,i,j;
                       ^
foo.cc:10:25: warning: unused variable 'f' [-Wunused-variable]
     long long a,b,c,d,e,f,g,n,i,j;
                         ^
foo.cc:10:27: warning: unused variable 'g' [-Wunused-variable]
     long long a,b,c,d,e,f,g,n,i,j;
                           ^
foo.cc:10:33: warning: unused variable 'j' [-Wunused-variable]
     long long a,b,c,d,e,f,g,n,i,j;
                                 ^
foo.cc:11:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%lld",&n);
     ~~~~~^~~~~~~~~~~
foo.cc:28:11: warning: 'a' may be used uninitialized in this function [-Wmaybe-uninitialized]
     printf("%lld",n/a);
     ~~~~~~^~~~~~~~~~~~

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