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  1. #include <iostream>
  2.  
  3. #include <sstream>
  4.  
  5. #include <string>
  6.  
  7.  
  8.  
  9. void validate(std::string const& a_str)
  10.  
  11. {
  12.  
  13.     std::cout << a_str << " is ";
  14.  
  15.     std::istringstream in(a_str);
  16.  
  17.     double val;
  18.  
  19.     if (in >> val && EOF == in.get()) std::cout << "valid\n";
  20.  
  21.     else std::cout << "invalid\n";
  22.  
  23. }
  24.  
  25.  
  26.  
  27. int main()
  28.  
  29. {
  30.  
  31.     validate("123.34ab");
  32.  
  33.     validate("123.34");
  34.  
  35.     return 0;
  36.  
  37. }
  38.  
  39.  
Success #stdin #stdout 0.02s 2860KB
comments (?)
stdin
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Standard input is empty
stdout
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123.34ab is invalid
123.34 is valid
https://ideone.com/gpPvu8
language:
C++ (gcc 8.3)
created:
11 years ago
visibility:
public

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