Task description

Write a function:

int solution(int A[], int N);

that, given a non-empty zero-indexed array A of N integers, returns the minimal positive integer that does not occur in A.

For example, given:

  A[0] = 1    
  A[1] = 3    
  A[2] = 6
  A[3] = 4    
  A[4] = 1    
  A[5] = 2

the function should return 5.

Assume that:

• N is an integer within the range [1..100,000];

• each element of array A is an integer within the range [2,147,483,648..2,147,483,647].

Complexity:

• expected worst-case time complexity is O(N);

• expected worst-case space complexity is O(N), beyond input storage (not counting the storage required for input arguments).

Elements of input arrays can be modified.

Solution C:20

int solution(int A[], int N) 
{
	int i = 0;


	int* temp = (int*)malloc(N*sizeof(int));
	for( i = 0; i < N; i++ )
	{
		temp[i] = 0x00;
	}

	for(  i = 0; i < N; i++ )
	{
		int position = A[i]-1;
		if(position >=0 && position < N )
		{
			temp[position] = 1;
		}
	}

	for( i = 0; i < N; i++ )
	{
		if(temp[i]==0)
		{
			break;
		}
	}

	free(temp);

	return i+1;
}