<p>Given a positive integer <code>n</code>, return the number of the integers in the range <code>[0, n]</code> whose binary representations <strong>do not</strong> contain consecutive ones.</p>

<p>&nbsp;</p>
<p><strong class="example">Example 1:</strong></p>

<pre>
<strong>Input:</strong> n = 5
<strong>Output:</strong> 5
<strong>Explanation:</strong>
Here are the non-negative integers &lt;= 5 with their corresponding binary representations:
0 : 0
1 : 1
2 : 10
3 : 11
4 : 100
5 : 101
Among them, only integer 3 disobeys the rule (two consecutive ones) and the other 5 satisfy the rule. 
</pre>

<p><strong class="example">Example 2:</strong></p>

<pre>
<strong>Input:</strong> n = 1
<strong>Output:</strong> 2
</pre>

<p><strong class="example">Example 3:</strong></p>

<pre>
<strong>Input:</strong> n = 2
<strong>Output:</strong> 3
</pre>

<p>&nbsp;</p>
<p><strong>Constraints:</strong></p>

<ul>
	<li><code>1 &lt;= n &lt;= 10<sup>9</sup></code></li>
</ul>

class Solution {
public:
    int t[33][3][3];
    int solve(int n,int i,int f,int prev){
        if(i==32)
            return 1;
        if(t[i][f][prev]!=-1)
            return t[i][f][prev];
        int ans=0;
        int ub=f?(n>>(31-i))&1:1;
        for(int k=0;k<=ub;k++){
            if(k && prev)
                continue;
            ans+=solve(n,i+1,f&(k==ub),k==1);
        }
        return t[i][f][prev]=ans;
    }
    string DecimalToBinary(int num)
    {
        string str;
        while(num){
            if(num & 1) // 1
                str+='1';
            else // 0
                str+='0';
            num>>=1; // Right Shift by 1  
        }    
        reverse(str.begin(),str.end());
        return str;
    }
    int findIntegers(int n) {
        // string temp=DecimalToBinary(n);
        memset(t,-1,sizeof(t));
        return solve(n,0,1,0);        
    }
};
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