help with the first C ++ "transport" problem

Question

#include <iostream>
using namespace std;

int main() {

int a;
int b=50;
int c;
int d;
int e;
cin>>a;
if (a<b){
e=b-a;
}else if (a>b){
c=a-b;
d=c-b;
e=b-d%b;
}else{
e=0;
}

cout<<e<<endl;
return 0;
}
why a test case is not right, what did I do wrong? (the test case is the third, the hidden one)

Answer 1

Your code is giving wrong output if
50 < a < 100.
For that, you can remove variable d and use variable c instead.

//int d
//d=c-b;
e=b-c%b;

Answer 2

#include <iostream>
using namespace std;

int main()
{
int no,x;
cin>>no;
cout<<50-(no%50);
return 0;
}

Answer 3

thank you all