Given 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 1Output:Sum of negative numbers is -41 Sum of even positive numbers is 60 Sum of odd positive numbers is 6Input:1 -1 50 -2 0 -3Output: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 ` `+` `=` `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 ` `+` `=` `num ` ` ` `else` `: ` ` ` ` ` `# add to positive 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) ` |

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**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. **

## 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 ` `+` `=` `num ` ` ` `# if positive number ` ` ` `else` `: ` ` ` ` ` `# if even positive ` ` ` `if` `(num ` `%` `2` `=` `=` `0` `): ` ` ` ` ` `# add to positive even sum ` ` ` `pos_even_sum ` `+` `=` `num ` ` ` `else` `: ` ` ` ` ` `# add to positive 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) ` |

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**Output: **

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

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