HDOJ 5143 NPY and arithmetic progression DFS

DFS.....

多余3个的数可以自己成等比数列

和其他数组合成等比数列的有1,2,3,  2,3,4  1,2,3,4 三种情况

NPY and arithmetic progression

Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 32768/32768 K (Java/Others)
Total Submission(s): 189    Accepted Submission(s): 61

Problem Description

NPY is learning arithmetic progression in his math class. In mathematics, an arithmetic progression (AP) is a sequence of numbers such that the difference between the consecutive terms is constant.(from wikipedia)
He thinks it's easy to understand,and he found a challenging problem from his talented math teacher:
You're given four integers,  a1,a2,a3,a4 , which are the numbers of 1,2,3,4 you have.Can you divide these numbers into some Arithmetic Progressions,whose lengths are equal to or greater than 3?(i.e.The number of AP can be one)
Attention: You must use every number exactly once.
Can you solve this problem?

 

Input

The first line contains a integer T — the number of test cases ( 1≤T≤100000 ).
The next T lines,each contains 4 integers  a1,a2,a3,a4(0≤a1,a2,a3,a4≤109) .

 

Output

For each test case,print "Yes"(without quotes) if the numbers can be divided properly,otherwise print "No"(without quotes).

 

Sample Input

   
   
   
   

    
    
    
    3
1 2 2 1
1 0 0 0
3 0 0 0
   
   
   
   

 

Sample Output

   
   
   
   

    
    
    
    Yes
No
Yes

    
    
    
    
 
     
 
      Hint 
     
In the first case,the numbers can be divided into {1,2,3} and {2,3,4}. In the second case,the numbers can't be divided properly. In the third case,the numbers can be divided into {1,1,1}. 
    
    
    
    
     
   
   
   
   

 

Source

BestCoder Round #22

 

/* ***********************************************
Author        :CKboss
Created Time  :2014年12月13日 星期六 23时09分55秒
File Name     :B_2.cpp
************************************************ */

#include <iostream>
#include <cstdio>
#include <cstring>
#include <algorithm>
#include <string>
#include <cstdlib>
#include <vector>
#include <queue>
#include <set>
#include <map>
#include <cmath>

using namespace std;

bool flag;

bool ck(int a,int b,int c,int d)
{
	/// check
	if(a==0&&b==0&&c==0&&d==0) return true;
	if( ((a!=0&&a>=3)||(a==0)) && ((b!=0&&b>=3)||(b==0)) && ((c!=0&&c>=3)||(c==0)) && ((d!=0&&d>=3)||(d==0)) ) return true;

	if(a-1>=0&&b-1>=0&&c-1>=0&&d-1>=0)
		if(ck(a-1,b-1,c-1,d-1)) return true;

	if(a-1>=0&&b-1>=0&&c-1>=0)
		if(ck(a-1,b-1,c-1,d)) return true;

	if(b-1>=0&&c-1>=0&&d-1>=0)
		if(ck(a,b-1,c-1,d-1)) return true;

	return false;
}

int main()
{
    //freopen("in.txt","r",stdin);
    //freopen("out.txt","w",stdout);

	int T_T;
	scanf("%d",&T_T);
	while(T_T--)
	{
		int a,b,c,d;
		scanf("%d%d%d%d",&a,&b,&c,&d);
		if(ck(a,b,c,d)==true) puts("Yes");
		else puts("No");
	}
    return 0;
}