foo.cc:17:8: error: stray '\20' in program
   17 |    if(a==t[i]){
      |        ^
foo.cc:32:7: error: stray '\20' in program
   32 |   if(b==6)t=t*10+9;
      |       ^
foo.cc:33:12: error: stray '\20' in program
   33 |   else if(b==9)t=t*10+6;
      |            ^
foo.cc:34:16: error: stray '\20' in program
   34 |   else t=t*10+b;
      |                ^

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