foo.cc: In function 'void dfs(int, int)':
foo.cc:20:1: error: expected 'while' before '}' token
 }
 ^
foo.cc:20:1: error: expected '(' before '}' token
foo.cc:20:1: error: expected primary-expression before '}' token
foo.cc:20:1: error: expected ')' before '}' token
foo.cc:20:1: error: expected ';' before '}' token
foo.cc:8:8: warning: unused variable 'y' [-Wunused-variable]
  int x,y,t,w,i;
        ^

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