## Python 3 program to print a right angled triangle :

In this tutorial, we will learn how to print one *right-angled triangle* using python 3. A triangle is called a right-angled triangle if it’s one angle is of *90 degrees* or *right angle*.

The other two angles depend on the *side length* of the triangle.

If the sides making the right angle are equal or if the triangle is an *isosceles triangle*, the other two angles will always *45 degrees*. If the sides are not equal, then the other two angles will be different.

In this tutorial, we will create one *isosceles right-angled triangle*, i.e. one angle is right angle, and the other two angles are *45* degrees.

Printing a *right-angled* triangle is an easier task than printing any other type of triangles programmatically. In this blog post, I will show you step by step on solving this problem programmatically.

The output will look as like below :

```
1
2 2
3 3 3
4 4 4 4
5 5 5 5 5
6 6 6 6 6 6
```

As you can see, we are actually printing the *rows* and *columns* here. By using *loops*, we can achieve results like this. We will run *two* loops. One for printing *rows* and one for *columns*.

For the *first* row, we need to print *one* column, *two* columns for the *second* row, *three* for the *third* row, etc.

You can use any loop (*for* or *while*) you want. In this example, we will use ‘*for*’ loop.

The outer loop will run for *6* times in this example. Let’s say it runs for i from *1 to 6.* The inner-loop will be used to print the numbers: it will run for *1 to i.*

- For
*i = 1*for outer loop,*j*will run for*1*for inner loop - For
*i = 2*for outer loop,*j*will run for*1,2*for inner loop - For
*i = 3*for outer loop,*j*will run for*1,2,3*for inner loop - For
*i = 4*for outer loop,*j*will run for*1,2,3,4*for inner loop - For
*i = 5*for outer loop,*j*will run for*1,2,3,4,5*for inner loop - For
*i = 6*for outer loop,*j*will run for*1,2,3,4,5,6*for inner loop

For each time the inner loop runs, we will print the value of *‘i’*. So, for *i = 1*, it will print only *1* , for *i = 2 ,* it will print only *2* etc.

Also, the inner loop will run for *‘i’* amount of time. For the *first* row, it will run for *one* time, *two* times for the *second* row, *three* for the *third* row etc. On each iteration of the inner loop, we are printing the character.

### Python Program :

```
#example 1
height = int(input("Enter the height of the triangle :"))
for i in range(1,height+1):
for j in range(1,i+1):
print(str(i)+" ", end='')
print()
```

**You can copy the programs from here.**

### Output:

The above program can be changed to print any type of right-angled triangle. e.g. you can print one right-angled triangle with the first row as *‘1’,* second row as *‘1,2’*, third row as *‘1,2,3’* etc.

Or you can use any other character to print the triangle like we are explaining below :

### Python program to print a right angle triangle using star (*) or any character :

We can modify the above program to print this triangle with any character we want :

```
#example 2
height = int(input("Enter the height of the triangle : "))
c = str(input("Enter the character you want to print the triangle : "))
for i in range(1,height+1):
for j in range(1,i+1):
print(c+" ", end='')
print()
```

### Sample Outputs :

As you can see, we can print triangles with any character that we want. Try to run the above program and drop one comment below if you have any queries.

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