C++ 中模运算符的正确用法

Question

I am trying to teach myself c++.

On Sololearn I have a task , which is

You are making a program for a bus service. A bus can transport 50 passengers at once. Given the number of passengers waiting in the bus station as input, you need to calculate and output how many empty seats the last bus will have.

Sample Input: 126

Sample Output: 24

It also says I should use the "%" operator. This is the code I created:

    int bus = 50;
    int stop;
    cin >> stop;
    cout<< stop % bus;
    return 0;

I get 12.

What is the correct way? I'm finding it difficult to understand what the modulo operator does. My understanding is that it divides as many times as it can and leaves the remainder (ie 16 % 3 = 1).

Answer 1

Modulos operator basically represents the leftover from the division

so what we need to do is take the number of people that will remain in the last bus travel which is stop % bus and compute bus - (stop % bus)

that way we know the number of empty seats on the last travel

This is like each bus was filled to the fullest (50 people per bus) what will remain is 26 and so on the last bus the number of empty seats will be 50 - 26 = 24

PS: 12 doesn't seem to be the right output of 126 % 50 it should be 26

Answer 2

First you have to get the number of passengers

int passengers; cin >> passengers;

then you have to find how many passengers are left

int remainPass = passengers % 50;

then you have to find how many seats are left

int remainSeats = 50 - remainPass;