Write a Python Program to Count Positive and Negative Numbers in a List using For Loop, While Loop, and Functions with a practical example.
Python Program to Count Positive and Negative Numbers in a List using For Loop
In this python program, we are using For Loop to iterate every element in a given List. Next, inside the for loop, we are using the If statement to check and count Positive and Negative numbers.
# Example
NumList = []
Positive_count = 0
Negative_count = 0
Number = int(input("Please enter the Total Number of List Elements: "))
for i in range(1, Number + 1):
value = int(input("Please enter the Value of %d Element : " %i))
NumList.append(value)
for j in range(Number):
if(NumList[j] >= 0):
Positive_count = Positive_count + 1
else:
Negative_count = Negative_count + 1
print("\nTotal Number of Positive Numbers in this List = ", Positive_count)
print("Total Number of Negative Numbers in this List = ", Negative_count)
In this Python program, the User entered Python List elements = [12, -22, 3, 5], Positive_count = 0, Negative_count = 0.
For Loop – First Iteration: for 0 in range(0, 4)
The condition is True. So, it enters into the Python If Statement
if(NumList[0] >= 0) => if(12 >= 0) – Condition is True
Positive_count = Positive_count + 1 => 0 + 1 = 1
Second Iteration: for 1 in range(0, 4) – Condition is True
if(NumList[1] >= 0) => if(-22 >= 0) – Condition is False, so it enters the Else block.
Negative_count = Negative_count + 1 => 0 + 1 = 1
Third Iteration: for 2 in range(0, 4) – Condition is True
if(NumList[2] >= 0) => if(3 >= 0) – Condition is True
Positive_count = 1 + 1 => 2
Fourth Iteration: for 3 in range(0, 4) – Condition is True
if(5 >= 0) – Condition is True. So, it enters into the Else block.
Positive_count = 2 + 1 => 3
Fifth Iteration: for 4 in range(4) – Condition is False. So, Python exits from For Loop.
Python Program to Count Positive and Negative Numbers in a List using While loop
This program for counting positive and negative numbers is the same as the above. We just replaced the Python For Loop syntax with the Python While statement.
NumList = []
Positive_count = 0
Negative_count = 0
j = 0
Number = int(input("Please enter the Total Number of List Elements: "))
for i in range(1, Number + 1):
value = int(input("Please enter the Value of %d Element : " %i))
NumList.append(value)
while(j < Number):
if(NumList[j] >= 0):
Positive_count = Positive_count + 1
else:
Negative_count = Negative_count + 1
j = j + 1
print("\nTotal Number of Positive Numbers in this List = ", Positive_count)
print("Total Number of Negative Numbers in this List = ", Negative_count)
count positive and negative list numbers using a while loop output is as shown below.
Please enter the Total Number of List Elements: 5
Please enter the Value of 1 Element : -3
Please enter the Value of 2 Element : -5
Please enter the Value of 3 Element : 9
Please enter the Value of 4 Element : 8
Please enter the Value of 5 Element : -6
Total Number of Positive Numbers in this List = 2
Total Number of Negative Numbers in this List = 3Python Program to Count Positive and Negative items in a List using Functions
This counting positive and negative list items program is the same as the first example. However, we separated the logic using Python Functions.
def count_Positive(NumList):
Positive_count = 0
for j in range(Number):
if(NumList[j] >= 0):
Positive_count = Positive_count + 1
return Positive_count
def count_Negative(NumList):
Negative_count = 0
for j in range(Number):
if(NumList[j] % 2 != 0):
Negative_count = Negative_count + 1
return Negative_count
NumList = []
Number = int(input("Please enter the Total Number of List Elements: "))
for i in range(1, Number + 1):
value = int(input("Please enter the Value of %d Element : " %i))
NumList.append(value)
Positive_cnt = count_Positive(NumList)
Negative_cnt = count_Negative(NumList)
print("\nTotal Number of Positive Numbers in this List = ", Positive_cnt)
print("Total Number of Negative Numbers in this List = ", Negative_cnt)
Please enter the Total Number of List Elements: 6
Please enter the Value of 1 Element : -11
Please enter the Value of 2 Element : -22
Please enter the Value of 3 Element : 33
Please enter the Value of 4 Element : 44
Please enter the Value of 5 Element : -55
Please enter the Value of 6 Element : 66
Total Number of Positive Numbers in this List = 3
Total Number of Negative Numbers in this List = 3Also Read