Figured it out, Thx for replies guys!
Code:
#include <stdio.h>
#include <stdlib.h>
#include <math.h>
int main(){
int A, B, C;
int x;
printf("Type in the integer lengths of 3 sides of a triangle:\n");
scanf("%d %d %d", &A, &B, &C);
if(A > B && A > C){ /*set largest value to C*/
x=A;
A=C;
C=x;}
if(B > A && B > C){
x=B;
B=C;
C=x;}
if(((int)A <= 0 || (int)B <= 0 || (int)C <= 0)||(A+B <= C)||(A+C<=B)||(B+C<=A)){ /*Is this a triangle?*/
printf("This is not a triangle.\n");
}
else if(A*A + B*B == C*C){
printf("This is a right-angled triangle.\n");
}
else if(A*A + B*B > C*C){
printf("This is an acute-angled triangle.\n");
}
else if (A*A + B*B < C*C){
printf("This is an obtuse-angled triangle.\n");
}
return 0;
}