C Program to Check Triangle is Valid or Not using Angles

Write a C Program to Check Triangle is Valid or Not using Angles. Any triangle is valid if the sum of the three angles in a triangle is equal to 180

C Program to Check Triangle is Valid or Not using Angles Example 1

This C program helps the user to enter all angles of a triangle. And then check whether it is valid or not using If Else.

/* C Program to Check Triangle is Valid or Not using Angles */
 
#include<stdio.h>
 
int main()
{
	int angle1, angle2, angle3, Sum;
 
  	printf("\n Please Enter Three Angles of a Triangle : ");
  	scanf("%d%d%d", &angle1, &angle2, &angle3);
  	
  	Sum = angle1 + angle2 + angle3;
  	
  	if(Sum == 180)
  	{
  		printf("\n This is a Valid Triangle");
 	}
	else
	{
		printf("\n This is an Invalid Triangle");
	}  
 	return 0;
 }
 Please Enter Three Angles of a Triangle : 45 75 60

 This is a Valid Triangle

Let me try another value

 Please Enter Three Angles of a Triangle : 60 50 90

 This is an Invalid Triangle

Program to Check Triangle is Valid or Not using Angles Example 2

In the above program, we forgot to check whether any of the angles is zero or not. It is also important while validating a triangle. So, we used a Logical AND operator in C Programming to make sure all angles are greater than 0

/* C Program to Check Triangle is Valid or Not using Angles */
 
#include<stdio.h>
 
int main()
{
	int angle1, angle2, angle3, Sum;
 
  	printf("\n Please Enter Three Angles of a Triangle : ");
  	scanf("%d%d%d", &angle1, &angle2, &angle3);
  	
  	Sum = angle1 + angle2 + angle3;
  	
  	if(Sum == 180 && angle1 != 0 && angle2 != 0 && angle3 != 0)
  	{
  		printf("\n This is a Valid Traingle");
 	}
	else
	{
		printf("\n This is an Invalid Triangle");
	}  
 	return 0;
 }
C Program to Check Triangle is Valid or Not using Angles 3

Now let me pass the correct angles

 Please Enter Three Angles of a Triangle : 70 70 40

 This is a Valid Triangle

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