foo.cc: In function 'int main()':
foo.cc:9:6: warning: this 'if' clause does not guard... [-Wmisleading-indentation]
    9 |      if(i%7==0||i%10==7||i/10==7)
      |      ^~
foo.cc:11:3: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'if'
   11 |   if(f==1)
      |   ^~
foo.cc:4:21: warning: unused variable 'b' [-Wunused-variable]
    4 |     int i=1,sum=0,n,b,c,f;
      |                     ^
foo.cc:4:23: warning: unused variable 'c' [-Wunused-variable]
    4 |     int i=1,sum=0,n,b,c,f;
      |                       ^

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