Why can’t I simply find the answer by `cout<<(input/5)+(input/25);`

please explain it to me somebody? Why do I need to divide it if I can find the answer by doing the above method. But if I am trying to do `(input/5)+(input/25)`

I am getting WA. Please help!

show us full code and problem link . single line of code doesnt determine error

you need to check for more higher powers of 5

because if n would be 1000 then multiples will be

`1000/5 + 1000/25 + 1000/125 + 1000/625 + 1000/3125 upto infinity`

but

all terms after 1000/3125 including it becomes zero, so sol is

`1000/5 + 1000/25 + 1000/125 + 1000/625`