OJ Board

Hi. Can anyone explain how we have to turn the dial? I follow steps with sample inputs and don't get correct answers.

Thanks.

you're probably rotating clockwise instead of counter-clockwise.
and vice versa.

Here is problem statement:

turn the dial clockwise 2 full turns
stop at the first number of the combination
turn the dial counter-clockwise 1 full turn
continue turning counter-clockwise until the 2nd number is reached
turn the dial clockwise again until the 3rd number is reached
pull the shank and the lock will open.

for example: 0 10 0 10
Initial position 0
2 full turns = 720 degree
stop at the first number 10 = 720 + 90 = 810
1 full turn and return to the same place = 810 + 360 = 1170
turning counter-clockwise from 1st position 10 to the 2nd 0 = 1170 + 90 = 1260
now the last turn clockwise from 2nd 0 to 3rd 10 = 1260 + 90 = 1350
The answer in sample output is 1890, but I didn't get the correct answer.

Which of this steps are wrong?

As konsept said: you're turning the wrong way around.
The answer is 720+270+360+270+270=1890.

I don't know why WA...but sample input gives correct answer...anyone help me....

#include <stdio.h>

void main(){
long int a, b, c, d, sum,temp;
while(scanf("%ld %ld %ld %ld",&a,&b,&c,&d)){
if(a==0&&b==0&&c==0&&d==0)break;
sum=1080;

temp=(a-b);
if(temp<0)temp=temp*(-1);

sum=sum+360-9*temp;

temp=(b-c);
if(temp<0)temp=temp*(-1);

sum=sum+360-9*temp;

temp=(c-d);
if(temp<0)temp=temp*(-1);

sum=sum+360-9*temp;

printf("%ld\n",sum);
}
}

Hi Xander,
Your technique is not quite correct. I have made few modifications and got it AC.

this part of your code is wrong :

if(temp<0)temp=temp*(-1);
sum=sum+360-9*temp

instead of multiplying by -1, add 40 to tmp if necessary.
and sum = sum + 9*temp;

Hope it helps.

Thanks sohel, but still got WA...

Can any one give me more sample input...I want to judge my program why this is WA?

Thanks Everyone

Xander,

Remember from 2nd number to 3rd number the lock is moved counter-clockwise. so instead of
temp=(b-c);---------> temp=(c-b);


change
[cpp]
sum=1080;

temp=(a-b);
if(temp<0)temp=temp*(-1);
sum=sum+360-9*temp;

temp=(b-c);
if(temp<0)temp=temp*(-1);
sum=sum+360-9*temp;

temp=(c-d);
if(temp<0)temp=temp*(-1);
sum=sum+360-9*temp
[/cpp]

to

[cpp]
sum=1080;

temp=(a-b);
if(temp<0)temp=temp+40;
sum=sum+9*temp;

temp=(c-b);
if(temp<0)temp=temp + 40;
sum=sum+9*temp;

temp=(c-d);
if(temp<0)temp=temp + 40;
sum=sum+9*temp
[/cpp]

hope it helps.

I'm confused with clockwise and counter-clockwise...

here is my code, and it's AC ...

But I still can't realise why ..... @_____@

[cpp]
#include <iostream>
using namespace std;
int turn (int a,int b,int d) {
if (d) { // clockwise
if (b>a) return (b-a);
else return (40-a+b);
}
else {
if (a>b) return (a-b);
else return (40-b+a);
}
}
int main() {
int a,b,c,d,s;
while (cin >>a>>b>>c>>d) {
if (!a&&!b&&!c&&!d) break;
s = 120;
s+=turn(a,b,0); // why here is counter-clockwise ?!
s+=turn(b,c,1);
s+=turn(c,d,0);
cout << s*9 << endl;
}
return 0;
}

[/cpp]

Thanks Sohel once again I got it AC now , you are a jennies man

Remember Always turn the dial

The only trick of this problem is distinguish between clockwise and
counter-clocwise.
Counting angle for clockwise is (start point) - ( end point )
Counting angle for counter clockwise is (end point) - (start point )

Good luck~

[cpp]#include <iostream.h>
#include <stdio.h>

int main()
{
int a,b,c,d,sum;
while(cin>>a>>b>>c>>d)
{
if(a==0&&b==0&&c==0&&d==0) break;
sum=1080+(120+a-2*b+2*c-d)*9;
cout<<sum<<endl;
}
return 0;
}[/cpp]

I dont know where goes wrong but I got WA all the time,can u give me some test data??thx!

You should write the code like this:
[cpp]#include <iostream>
using namespace std;

/* code */

[/cpp]
1) there is no need to include stdio, if you use only cin and cout
2) declaration of iostream was wrong - but this cause only warning message

And the major problem, you calculate the output in wrong way. Try this:

5 15 35 5
5 15 25 35
0 0 0 0

Output for this test is:

1800
1710