Why does Java output 50 while C++ outputs 51 for the same code concept?
int i=5;
i= (++i + ++i + ++i + ++i + ++i + i++);
print i
Java: 50
C++: 51
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What is the real purpose of this statement `(++i + ++i + ++i + ++i + ++i + i++);` ? – Pradeep Simha Apr 05 '17 at 12:01
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Similar/dupe [here](http://stackoverflow.com/questions/949433/why-are-these-constructs-using-undefined-behavior) – WhiZTiM Apr 05 '17 at 12:07
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Because Java tries to make sense out of nonsensical statements like that one, and C++ doesn't. – Pete Becker Apr 05 '17 at 12:15
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Possible duplicate of [Why are these constructs (using ++) undefined behavior?](http://stackoverflow.com/questions/949433/why-are-these-constructs-using-undefined-behavior) – Richard Critten Apr 05 '17 at 13:22
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This question is in the __"What NOT to ask"__ section: http://stackoverflow.com/tags/c%2b%2b/info – Richard Critten Apr 05 '17 at 13:23
1 Answers
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The results are different because the lauguages are specified differently.
why java says 50
Because the order of evaluation is defined so in Java. The addition is: 6+7+8+9+10+10 == 50. The final post increment is overwritten by the assignment and has no effect.
while c++ says 51
The shown program has undefined behaviour in C++, so it could have any output. It happened to be 51 in this case. More details in this answer: https://stackoverflow.com/a/4176333/2079303
