C program Boundary Value Analysis - Nature of roots of a quadratic equation

#include <stdio.h> #define MIN 0 #define MAX 100 void test(int a, int b, int c) { char *output = ""; if(a == 0) { output = "Not a Quadratic Equation\n"; } else { int d = b*b - 4*a*c; if(d < 0) { output = "Imaginary Roots\n"; } else if(d == 0) { output = "Real and Equal Roots\n"; } else { output = "Real and Distinct Roots\n"; } } printf("%d\t%d\t%d\t%s",a,b,c,output); } int main(void) { int min, max; printf("Enter range\n"); scanf("%d%d",&min,&max); if(min < MIN || max > MAX) { printf("Invalid range\n"); return 0; } int nominal = (min + max)/2; int values[] = {min, min+1, nominal, max-1, max}; printf("a\tb\tc\tOutput\n"); // fix variable b,c to nominal value and change values of a for(int i=0;i<5;i++) { test(values[i],nominal, nominal); } //fix variable a,c to nominal value and change values of b for(int i=0;i<5;i++) { // skip the case where all three values of a,b,c are same // since it was already included once in above loop if(values[i] != nominal) test(nominal, values[i], nominal); } // fix variable a,b to nominal values and change values of c for(int i=0;i<5;i++) { if(values[i] != nominal) test(nominal, nominal, values[i]); } return 0; }

STQA nature of roots program.