#include <iostream> using namespace std; int main() { int a; for ( a = 10; a <= 100; a+=10){ cout << a << endl;

Question

the output of the above program is 10
20
..100
but it says...a= 10;a<=100(true);a=a+10(20)
cout << a;
a= 20...isn't it??
why the output is starting with 10??

Answer 1

For loop execution takes as follows:
1. Initialization of variable
2.The condition statements
3.If condition statements is true the code inside for will be executed.
4. After executing the code inside for loop at last the variable is incremented/decremented.

So in your case after initializing (variable a=20) and checking condition(a<=100 which is true) it will execute code inside the for loop. so it prints 10 everytime you run the code. and then after printing 10 the variable a is incremented !!

Answer 2

output starts with 10 because that is the intial condition of the for loop

Answer 3

In a for loop, the increment section is typically performed last, so a=10 in the first pass through the interior of the loop.

This might seem a bit counterintuitive to start (since that part is defined before the repeated code), but try rewriting this as a while, and move the a+=10 statement around among the other statements.

Answer 4

the given program will give the first value of a is 10 as it is the initial value of a that's why it (program )gives the output as 10

Answer 5

coz the need to start is first variable
default to start
so if that start from 20 it's mean
20
40
...
100