Consensus--i+++j how to calculate?

This is an interesting calculation, and the 3 plus sign is connected. So, how is it combined? Is it based on: i + (++j), or according to (i++) + J to calculate?

This is not much of a problem in a similar way to C + +, because C + + relies on the hardware structure of the implementation and different environmental outcomes. In Java, however, the result is fixed and unaffected by the hardware environment and platform in which it runs.

In what order to calculate, write a program to test it.

Combination of "example" + +
　

If combined as:
　　

The value of J is added 1, and the value of the result K is 31. The results of the program run as follows:
　　

From the results, the order of Union is the former, that is to say
　　

Equivalent:

For clarity, parentheses are used here.

　　Greedy rules

This binding is rooted in the greedy rules of the compiler, which means that when parsing symbols, the compiler will combine as many valid symbols as possible, such as the expression above:

"+" and "+ +" are valid symbols, but "+ + +" is not a valid symbol, so after analysis, the expression is resolved to:

However, the compiler is extremely "greedy" by combining as many valid symbols as possible, regardless of whether this combination conforms to the rules of the grammar, such as an expression:

Originally, we originally intended to be a minus? B, namely:

However, if you do not use spaces (or other white space separators that conform to grammatical rules) or parentheses, after parsing, because the symbol "–" is a valid symbol, it is grouped together so that the structure is divided into:

This, of course, does not conform to grammatical rules, so the compiler will ruthlessly generate compilation errors.

　　Why greed?

Perhaps the reader will ask: Why use this greedy way to analyze characters? So what good is this? believe that you have seen the following example, you will understand.

"Example" the greedy explanation.

The program is to output several octal escape characters, seemingly not related to the greedy rules at all. If you think so, then you are wrong, see the results of the operation:

Consider why the length of the String object "\17" is 1, and the length of "\171" is 1? Also, why "\171" does not print out the "\17" escape character "" and connects to "1":

Instead, print out:

? That's because of the greedy rules, the compiler will combine as many valid characters as possible, otherwise the escape character will lose its effect. For "\1717" and "\431", it is handled by two characters, because both values exceed the range (\0~\377) of the octal escape character, so \1717 resolves to \171 and 7, and the emphasis content and \431 resolves to "\43" and "1".

　　Summarize:

When parsing characters, the compiler combines as many valid characters as possible. and "excessive" greed, regardless of whether this combination is in line with grammatical rules.

Greedy rules are useful because they allow for special handling of escape characters.
　　
　　
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Consensus--i+++j how to calculate?