CHFGCD - Editorial

OMG this was a bad mistake , thanks for the help.

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Why 7 27 output is 2 instead of 1?
gcd(7, 28) is 7 > 1

It should be 1 - where are you seeing that the output should be 2?

sorry my bad :upside_down_face:

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though used the same approach but could not get ac. can any one explain what was my mistake?
my code - Fj10CB - Online C++0x Compiler & Debugging Tool - Ideone.com

It fails on the test input:

1
5 21

Try this
1
3 5

Output should be 1 but your code outputs 2

but my code is giving ans 2 for 5 and 21. isn’t correct?

No: 5+1=6, and \gcd(6,21)=3.

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Please Help. Why is this giving WA. Cant think of any case it will fail.
#include <bits/stdc++.h>
using namespace std;
#define ll long long

int main() {
int t;cin>>t;
while(t–)
{
ll x,y,c=0;cin>>x>>y;
while(__gcd(x,y)==1)
{
if(x<y)swap(x,y);
if(x%2==0)y++;
else x++;
c++;
}
cout<<c<<endl;
}
}

https://www.codechef.com/viewsolution/49217035
Pls help it’s giving me TLE

Maybe stop running sieve()?

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17 29 becomes 18 and 30 after 2 operations then gcd(18,30)>1… We can change both values but in different operation.

Didnt’t worked for me…still giving me TLE…pls help

For god sake, watch your code - the indentation sucks. Provide a cleaner code. It becomes easy to find out where it went wrong.

https://www.codechef.com/viewsolution/49222720
Why my solution giving WA ? Giving correct answers when testing for all combinations of even and odd numbers.

You didn’t test all combinations.

Try this test case:

Input

1
3 9

Expected Output

0

Your Output

2

It should be mentioned in the question that we can change both the numbers.

It is clearly written.

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