foo.cc:145:4: warning: "/*" within comment [-Wcomment]
  145 |  } /*
      |     
foo.cc: In function 'int main()':
foo.cc:285:6: warning: unused variable 'a' [-Wunused-variable]
  285 |  int a,b,n=0,i=0,s=0;
      |      ^
foo.cc:285:8: warning: unused variable 'b' [-Wunused-variable]
  285 |  int a,b,n=0,i=0,s=0;
      |        ^

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