Question

how this inerement and decerement operator works in c,bcoz inmgetting difrent output in c and java

Answer 1

in both languages, increment can be written as
i++, ++i , i+=1, i=i+1
However, note that i++ and ++i are slightly different

Answer 2

Pre and post increment/decrement operators both work the same in C, C++, Java, JavaScript and a bunch of other languages.

i = 0;

++i; // will evaluate to 1, this is pre-increment, the increment happens before i is evaluated

i++; // will evaluate to 1, this is post-increment, i is evaluated, then incremented

// now i == 2

The decrement operators are the same.