c - Increment and Decrement Operators -

#include <stdio.h>  int main() {   int x = 4, y, z;   y = --x;   z = x--;   printf("%d %d %d", x, y, z); } 

output: 2 3 3

can explain this?
, i =+ j mean (suppose i = 1 , j = 2)?

simple explanation:

--x or ++x : value modified after.

x-- or x++ : value modified before

detailed explanation:

--x or ++x: pre-decrement/increment: first operation of decrementing or incrementing first, assign x.

x-- or x++: post:decrement/increment: first assign value of x , operation of decrementing or incrementing after.

lets write code in nicer format , go through code step step , annotate show visually happens:

main() {     //we declare variables x, y , z, x given value of 4.     int x=4,y,z;      //--x decrement var x 1 first assign value of x y.     //so: x = 3, y = 3 , z = nothing yet.     y = --x;      //x-- assign value of x z first, var x decremented 1 after.     //so: x = 2, y=3 , z = 3     z = x--;       printf ("\n %d %d %d", x,y,z);  }