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# Python Program to find Sum of Negative, Positive Even and Positive Odd numbers in a List

• Last Updated : 06 Feb, 2023

AuxilaoGiven a list. The task is to find the sum of Negative, Positive Even, and Positive Odd numbers present in the List.

Examples:

```Input: -7 5 60 -34 1
Output:
Sum of negative numbers is  -41
Sum of even positive numbers is  60
Sum of odd positive numbers is  6

Input: 1 -1 50 -2 0 -3
Output:
Sum of negative numbers is  -6
Sum of even positive numbers is  50
Sum of odd positive numbers is  1```

Negative numbers are the numbers less than 0 while positive even numbers are numbers greater than 0 and also divisible by 2. 0 is assumed to be a positive even number, in this case.

Approach:

• The first approach input a list of numbers from the user.
• Two loops are run, one for the positive numbers and the other for the negative numbers, computing the numbers’ summation.
• If n is the size of the list of numbers,
• it takes O(2n) time complexity, for iterating over the list of numbers twice.

## Python3

 `class` `Sumofnumbers:` `    ``# find sum of negative numbers``    ``def` `negSum(``self``, ``list``):` `        ``# counter for sum of``        ``# negative numbers``        ``neg_sum ``=` `0` `        ``for` `num ``in` `list``:` `            ``# converting number``            ``# to integer explicitly``            ``num ``=` `int``(num)` `            ``# if negative number``            ``if``(num < ``0``):` `                ``# simply add to the``                ``# negative sum``                ``neg_sum ``=` `neg_sum ``+` `num` `        ``print``(``"Sum of negative numbers is "``, neg_sum)` `    ``# find sum of positive numbers``    ``# according to categories``    ``def` `posSum(``self``, ``list``):` `        ``# counter for sum of``        ``# positive even numbers``        ``pos_even_sum ``=` `0` `        ``# counter for sum of``        ``# positive odd numbers``        ``pos_odd_sum ``=` `0``        ``for` `num ``in` `list``:` `            ``# converting number``            ``# to integer explicitly``            ``num ``=` `int``(num)` `            ``# if negative number``            ``if``(num >``=` `0``):` `                ``# if even positive``                ``if``(num ``%` `2` `=``=` `0``):` `                    ``# add to positive``                    ``# even sum``                    ``pos_even_sum ``=` `pos_even_sum ``+` `num``                ``else``:` `                    ``# add to positive odd sum``                    ``pos_odd_sum ``=` `pos_odd_sum ``+` `num` `        ``print``(``"Sum of even positive numbers is "``,``              ``pos_even_sum)` `        ``print``(``"Sum of odd positive numbers is "``,``              ``pos_odd_sum)`  `# input a list of numbers``list_num ``=` `[``-``7``, ``5``, ``60``, ``-``34``, ``1``]` `# creating an object of class``obj ``=` `Sumofnumbers()` `# calling method for  sum``# of all negative numbers``obj.negSum(list_num)` `# calling method for``# sum of all positive numbers``obj.posSum(list_num)`

Output

```Sum of negative numbers is  -41
Sum of even positive numbers is  60
Sum of odd positive numbers is  6```

The second approach computes the sum of respective numbers in a single loop. It maintains three counters for each of the three conditions, checks the condition and accordingly adds the value of the number in the current sum . If n is the size of the list of numbers, it takes O(n) time complexity, for iterating over the list of numbers once.

Space complexity:
The space complexity of the Sumofnumbers class is O(1). This is because the class does not store any additional data and only uses the given list as an input.

## Python3

 `class` `Sumofnumbers:``    ``# find sum of numbers``    ``# according to categories``    ``def` `Sum``(``self``, ``list``):` `        ``# counter for sum``        ``# of negative numbers``        ``neg_sum ``=` `0` `        ``# counter for sum of``        ``# positive even numbers``        ``pos_even_sum ``=` `0` `        ``# counter for sum of``        ``# positive odd numbers``        ``pos_odd_sum ``=` `0` `        ``for` `num ``in` `list``:` `            ``# converting number``            ``# to integer explicitly``            ``num ``=` `int``(num)` `            ``# if negative number``            ``if``(num < ``0``):` `                ``# simply add``                ``# to the negative sum``                ``neg_sum ``=` `neg_sum ``+` `num``            ``# if positive number``            ``else``:` `                ``# if even positive``                ``if``(num ``%` `2` `=``=` `0``):` `                    ``# add to positive even sum``                    ``pos_even_sum ``=` `pos_even_sum ``+` `num``                ``else``:` `                    ``# add to positive odd sum``                    ``pos_odd_sum ``=` `pos_odd_sum``+``num``        ``print``(``"Sum of negative numbers is "``,``              ``neg_sum)``        ``print``(``"Sum of even positive numbers is "``,``              ``pos_even_sum)``        ``print``(``"Sum of odd positive numbers is "``,``              ``pos_odd_sum)`  `# input a list of numbers``list_num ``=` `[``1``, ``-``1``, ``50``, ``-``2``, ``0``, ``-``3``]` `# creating an object of class``obj ``=` `Sumofnumbers()` `# calling method for``# largest sum of all numbers``obj.``Sum``(list_num)`

Output

```Sum of negative numbers is  -6
Sum of even positive numbers is  50
Sum of odd positive numbers is  1```

Time Complexity: O(n) ,The time complexity of this algorithm is O(n) as it loops over all the numbers in the list and checks each of them to determine whether they are negative, even, or odd.

Space Complexity: O(1) ,The space complexity of this algorithm is O(1) as we are not creating any additional data structures or arrays. We are simply keeping track of the sums of all the numbers in the list and updating them as we loop through the list.

## Python3

 `lst ``=` `[``1``, ``-``1``, ``50``, ``-``2``, ``0``, ``-``3``];i``=``0``x``=``[i ``for` `i ``in` `lst ``if` `i>``0` `and` `i``%``2``=``=``0``]``y``=``[i ``for` `i ``in` `lst ``if` `i>``0` `and` `i``%``2``!``=``0``]``z``=``[i ``for` `i ``in` `lst ``if` `i<``0``]``print``(``"even positive numbers sum"``,``sum``(x))``print``(``"odd positive numbers sum"``,``sum``(y))``print``(``"negative numbers sum"``,``sum``(z))`

Output

```even positive numbers sum 50
odd positive numbers sum 1
negative numbers sum -6```

## Python3

 `lst ``=` `[``1``, ``-``1``, ``50``, ``-``2``, ``0``, ``-``3``]``x``=``list``(``filter``(``lambda` `i: (i>``0` `and` `i``%``2``=``=``0``),lst))``y``=``list``(``filter``(``lambda` `i: (i>``0` `and` `i``%``2``!``=``0``),lst))``z``=``list``(``filter``(``lambda` `i: (i<``0``),lst))``print``(``"even positive numbers sum"``,``sum``(x))``print``(``"odd positive numbers sum"``,``sum``(y))``print``(``"negative numbers sum"``,``sum``(z))`

Output

```even positive numbers sum 50
odd positive numbers sum 1
negative numbers sum -6```

## Python3

 `lst ``=` `[``'1'``, ``'-1'``, ``'50'``, ``'-2'``,``' 0'``, ``'-3'``]``x``=``[``int``(i) ``for` `a,i ``in` `enumerate``(lst) ``if` `int``(i)``%``2``=``=``0` `and` `int``(i)>``0``]``y``=``[``int``(i) ``for` `a,i ``in` `enumerate``(lst) ``if` `int``(i)``%``2``!``=``0` `and` `int``(i)>``0``]``z``=``[``int``(i) ``for` `a,i ``in` `enumerate``(lst) ``if` `int``(i)<``0``]``print``(``"even positive numbers sum"``,``sum``(x))``print``(``"odd positive numbers sum"``,``sum``(y))``print``(``"negative numbers sum"``,``sum``(z))`

Output

```even positive numbers sum 50
odd positive numbers sum 1
negative numbers sum -6```

## Python3

 `def` `recursive_sum(lst, i``=``0``, x``=``[], y``=``[], z``=``[]):` `    ``if` `i ``=``=` `len``(lst):` `        ``return` `(``sum``(x), ``sum``(y), ``sum``(z))` `    ``elif` `lst[i] > ``0` `and` `lst[i] ``%` `2` `=``=` `0``:` `        ``x.append(lst[i])` `    ``elif` `lst[i] > ``0` `and` `lst[i] ``%` `2` `!``=` `0``:` `        ``y.append(lst[i])` `    ``elif` `lst[i] < ``0``:` `        ``z.append(lst[i])` `    ``return` `recursive_sum(lst, i``+``1``, x, y, z)` `lst ``=` `[``1``, ``-``1``, ``50``, ``-``2``, ``0``, ``-``3``]` `x,y,z ``=` `recursive_sum(lst)` `print``(``"even positive numbers sum"``,x)` `print``(``"odd positive numbers sum"``,y)` `print``(``"negative numbers sum"``,z)` `#This code is contributed by vinay pinjala.`

Output

```even positive numbers sum 50
odd positive numbers sum 1
negative numbers sum -6```

Time Complexity: O(n), because n recursive calls are made.
Auxiliary Space: O(n), because of n recursive calls are made and each recursive call is pushed into stack.

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