foo.cc:143:4: warning: "/*" within comment [-Wcomment]
  143 |  } /*
      |     
foo.cc: In function 'int main()':
foo.cc:227:8: warning: unused variable 'b' [-Wunused-variable]
  227 |  int a,b,c,d=0,i,j,n,m,x,sum=0;
      |        ^
foo.cc:227:10: warning: unused variable 'c' [-Wunused-variable]
  227 |  int a,b,c,d=0,i,j,n,m,x,sum=0;
      |          ^

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