<p>Given an integer array <code>nums</code>, return <em>the maximum difference between two successive elements in its sorted form</em>. If the array contains less than two elements, return <code>0</code>.</p>

<p>You must write an algorithm that runs in linear time and uses linear extra space.</p>

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

<pre>
<strong>Input:</strong> nums = [3,6,9,1]
<strong>Output:</strong> 3
<strong>Explanation:</strong> The sorted form of the array is [1,3,6,9], either (3,6) or (6,9) has the maximum difference 3.
</pre>

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

<pre>
<strong>Input:</strong> nums = [10]
<strong>Output:</strong> 0
<strong>Explanation:</strong> The array contains less than 2 elements, therefore return 0.
</pre>

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

<ul>
	<li><code>1 &lt;= nums.length &lt;= 10<sup>5</sup></code></li>
	<li><code>0 &lt;= nums[i] &lt;= 10<sup>9</sup></code></li>
</ul>

class Solution {
public:
    unordered_map<int,int> C;
    int power(int n,int i){
        if(i==0){
            return 1;
        }
        if(C.count(i)==1){
            return C[i];
        }
        C[i]=n*power(n,i-1);
        return C[i];
    }
    void radix_sort(vector<int>& nums){
        int maxi=nums[0];
        for(int i=1;i<nums.size();i++){
            maxi=max(maxi,nums[i]);
        }
        int n=0;
        while(maxi!=0){
            maxi=maxi/10;
            n++;
        }
        unordered_map<int,vector<int>> Buckets;
        int index;
        int curr=0;
        for(int i=0;i<n;i++){
            for(auto& J:nums){
                index=(J/power(10,i));
                index=index%10;
                Buckets[index].push_back(J);
            }
            curr=0;
            for(int l=0;l<10;l++){
                for(auto& I:Buckets[l]){
                    nums[curr]=I;
                    curr++;
                }
                Buckets[l]={};
            }
        }
    }
    int maximumGap(vector<int>& nums) {
        if(nums.size()<2){
            return 0;
        }
        radix_sort(nums);
        int val=0;
        for(int i=1;i<nums.size();i++){
            val=max(val,nums[i]-nums[i-1]);
        }
        return val;
    }
};
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