<p>Given an integer array <code>nums</code> and an integer <code>k</code>, modify the array in the following way:</p>

<ul>
	<li>choose an index <code>i</code> and replace <code>nums[i]</code> with <code>-nums[i]</code>.</li>
</ul>

<p>You should apply this process exactly <code>k</code> times. You may choose the same index <code>i</code> multiple times.</p>

<p>Return <em>the largest possible sum of the array after modifying it in this way</em>.</p>

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

<pre>
<strong>Input:</strong> nums = [4,2,3], k = 1
<strong>Output:</strong> 5
<strong>Explanation:</strong> Choose index 1 and nums becomes [4,-2,3].
</pre>

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

<pre>
<strong>Input:</strong> nums = [3,-1,0,2], k = 3
<strong>Output:</strong> 6
<strong>Explanation:</strong> Choose indices (1, 2, 2) and nums becomes [3,1,0,2].
</pre>

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

<pre>
<strong>Input:</strong> nums = [2,-3,-1,5,-4], k = 2
<strong>Output:</strong> 13
<strong>Explanation:</strong> Choose indices (1, 4) and nums becomes [2,3,-1,5,4].
</pre>

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

<ul>
	<li><code>1 &lt;= nums.length &lt;= 10<sup>4</sup></code></li>
	<li><code>-100 &lt;= nums[i] &lt;= 100</code></li>
	<li><code>1 &lt;= k &lt;= 10<sup>4</sup></code></li>
</ul>

class Solution {
public:
    int largestSumAfterKNegations(vector<int>& nums, int k) {
        int count=0;
        int sum=0;
        vector<int>record;
        for(int i=0;i<nums.size();i++){
            record.push_back(abs(nums[i]));
        }
        sort(record.begin(),record.end());
        int min=record[0];
        for(int i=0;i<nums.size();i++){
            if(nums[i]<0)count++;
        }
        sort(nums.begin(),nums.end());
        for(int i=0;i<nums.size();i++){
            if(k==count && nums[i]<0){
                nums[i]=abs(nums[i]);
            }
            else if(k>count){
              int x=k-count;
              for(int i=0;i<count;i++){
                nums[i]=abs(nums[i]);

              }
              if(x%2==0){
                nums[i]=nums[i];
              }
            //   else if(x%2!=0){
            //     sort(nums.begin(),nums.end());
            //     nums[0]=-nums[0];
            //   }
            }
            else{
                for(int i=0;i<k;i++){
                    nums[i]=abs(nums[i]);
                }
            }
        }
        sort(nums.begin(),nums.end());
        for(int i=0;i<nums.size();i++){
            if(k>count){
                int y=k-count;
                if(y%2!=0){
                    int z=nums[0];
                    z=z*(-1);
                    nums[0]=z;
                    break;
                }
            }
        }
        for(int i=0;i<nums.size();i++){
            sum+=nums[i];
        }
        return sum;
        
    }
};
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