foo.cc: In function 'int main()':
foo.cc:44:9: error: 'ans' was not declared in this scope; did you mean 'abs'?
   44 |         ans=0x80000000;
      |         ^~~
      |         abs
foo.cc:43:15: warning: unused variable 'v' [-Wunused-variable]
   43 |         int u,v;
      |               ^

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