forming triangle using the given values in c

Question

I want to check if the given valued are valid to form a triangle using c program. this is what I have written so far :

#include <stdio.h>

int main()

{

float a,b,c,f1,f2,f3;

printf("Input the three floating point values of the triangle: ");

scanf("%f%f%f",&a,&b,&c);

f1=a+b;

f2=b+c;

f3=c+a;

    if(f1<=c || f2<=a || f3<= b)

    {

    printf("the values are not valid to form a triangle");

}

else{

printf("the values are valid\n");

}

return 0;

}

Here should I use if(f1<=c && f2<=a && f3<= b)  instead of   if(f1<=c || f2<=a || f3<= b) ? if so why?

Answer 1

You have to confirm if all the numbers total is equal to 180º, if so, this is a triangle, if not, it isn't. Simpler as that.

I've made an example for you:

#include <stdio.h>

int main() {
    float a,b,c,f1,f2,f3;
    
    printf("Input the three floating point values of the triangle: ");
    scanf("%f%f%f",&a,&b,&c);
    
    if (a + b + c == 180){
        printf("the values are valid\n");  
    } else {
        printf("the values are not valid to form a triangle");
    }
    return 0;
}

I used some parts of what u made.

Ur welcome :)

In this language, "&&" mean "And" and "||" mean "or".