foo.cc: In function 'int IO::read()':
foo.cc:25:9: warning: this 'while' clause does not guard... [-Wmisleading-indentation]
   25 |         while(ch<='9'&&ch>='0')x=x*10+ch-'0',ch=gc();return x*f;
      |         ^~~~~
foo.cc:25:54: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'while'
   25 |         while(ch<='9'&&ch>='0')x=x*10+ch-'0',ch=gc();return x*f;
      |                                                      ^~~~~~

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