foo.c: In function 'main':
foo.c:6:20: warning: unused variable 'i' [-Wunused-variable]
  long long int n,m,i=1;
                    ^
foo.c:7:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%lld",&n);
  ^~~~~~~~~~~~~~~~
foo.c:6:18: warning: 'm' may be used uninitialized in this function [-Wmaybe-uninitialized]
  long long int n,m,i=1;
                  ^

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