Help in VIIT CP-DIZHARD Division question

1

can someone help me with this question?
question link - CodeChef: Practical coding for everyone
my approach is this. I’m not getting the answer.
thank you in advabce

#include<bits/stdc++.h>
typedef long long ll;
#define endl "\n"
using namespace std;

ll sum(ll n)
{
ll m,sum=0;
while(n>0)    
 {    
  m=n%10;    
  sum=sum+m;    
  n=n/10;    
 } 
return sum;
}

void sol()
{
  ll  k,a,b;
  cin>>k>>a>>b;// example - 6 10 7
  long double x= (a/b);// 1 
  long double f=  double(a)/ double(b); // 1.42857
  long double removed_part = (f-x);// 1.42857 - 1 = 0.42857

  long double ok =removed_part*pow(10,k); //   428571 

 string temp = to_string(ok); // in string 42857
 string r = temp.substr(0, k); //extract the first k  charcters

 ll xx= stoll(r);// to int
 cout<<sum(xx)<<endl;
}
 

int main()
{
  ios::sync_with_stdio(false);
  cin.tie(NULL);cout.tie(NULL); 
 int t=1;
 cin>>t;
 while(t--)
 {
   sol();  
 }  
return 0;
}
2

Try this test case
1
200 2 3

1 Like
3

T=int(input())

for i in range(T):
K=int(input())
A,B=map(int,input().split())
x=A/B
n=x-1
H=round(n,K)
H=H*(10**K)

sum=0
i=0
while(H!=0):
    sum=sum+H%10
    H=H//10
    i=i+1
print(int(sum))

Op:
1
200
2 3
763

1 Like
4

I think when you do this,

might just result in an overflow as (1<=k<=500).
You can do this in an alternate way like this (it’s just a normal implementation of school level division).

void solve(){
int t;
cin>>t;
while(t–){
int k,a,b,rem,temp=0,sum=0;
cin>>k>>a>>b;
rem=a%b;
if(rem){
rem*=10;
while(temp!=k){
// cout<<rem/b<<" ";
sum+=rem/b;
rem%=b;
rem*=10;
temp++;
}
}
cout<<sum<<nl;
}
}

Hope this helps :slight_smile:

1 Like
5

yep , out of bounds

6

thanks vats, :smiley: