foo.cpp: In function 'int RD()':
foo.cpp:5:2: warning: this 'while' clause does not guard... [-Wmisleading-indentation]
  while( (cr=getchar())<'0' || cr>'9');res=cr-'0';
  ^~~~~
foo.cpp:5:39: note: ...this statement, but the latter is misleadingly indented as if it is guarded by the 'while'
  while( (cr=getchar())<'0' || cr>'9');res=cr-'0';
                                       ^~~