C++ while loops and for loops not working - c++

Question

First, I'll send the code.
#include <iostream>
using namespace std;
int main() {
int times = 0;
cout << "Enter a number of candies:";
int number;
cin >> number;
while (number >= 1000) {
cout << "Please enter an integer number between 0 and 999.\n";
cin >> number;
}
for (times <= 10; times++; number--) {
cout << "nomnom I have" << number - 1 << "candies left.\n";
}
}
I am trying to practice c++ because I'm a beginner so I made a little program that is supposed to allow you to enter a number between 1 and 999, then this is gonna be the number of candies. Then, it says how many there are left. It's not working though. Can anyone tell me why? Thanks.

Answer 1

You should have your for loop formatted like this:
for (; times <= 10; times++, number--) {
cout << "nomnom I have" << number - 1 << "candies left.\n";
}
The format of the for loop follows the following rule:
for(<initializer, which you can skip> ; <condition for execution which is required> ; <increment or decrement of the variable which you are bounding with the condition, this part is not required either>)
Within the initializer part you can create multiple variables, you just need to separate them with a ",", the same rule applies to the final part of the for loop. Neither the initializer not the modifier at the end are required for correct syntax. This is a valid example:
int i = 0;
for(; i < 5;)
{
++i;
}
For example:
for(int i = 0, j = 5; i < 5 && j > 0; ++i, --j){}
int i = 0, j = 5;
for(; i < 5 && j > 0; ++i, --j){}
int i = 0, j = 5;
for(; i < 5 && j > 0;){
++i;
--j;
}
All of these examples are accomplishing the same task of incrementing i and decrementing j.

Answer 2

Your for loop is incorrect - it should be done according to this:
for( <initialization> ; <checking> ; <run_in_each_loop> ){ ...}
You can read more about for loop here.
You want your code to do 2 "increments" (<run_in_each_loop>). You can't do this using ; in between
A common idiom is to use the comma operator which evaluates both
operands, and returns the second operand. Thus:
for(int i = 0; i != 5; ++i,++j)
do_something(i,j);
read more here.
Other way would be to put number-- inside of { ... } brackets.
In the end, your code should look like that:
#include <iostream>
using namespace std;
int main() {
int times = 0;
cout << "Enter a number of candies:";
int number;
cin >> number;
while (number >= 1000) {
cout << "Please enter an integer number between 0 and 999.\n";
cin >> number;
}
for ( ; times <= 10; times++, number--) {
cout << "nomnom I have" << number << "candies left.\n";
}
return;
}

Answer 3

You're pretty close! There was just a slight issue with the for loop syntax:
The first part of the for loop is actually the initializer, the middle bit is the conditional, and the last bit is the iterator, it's a bit different than the while loop.
Here is what you probably meant to do:
for (times = 0; times < 9; number--, times++) {
cout << "nomnom I have" << number - 1 << "candies left.\n";
}