#include<stdio.h>
#include<stdlib.h> 
#include <time.h>
#define N 5
int main(){
    int x, n;
    
    srand(time(0));
    
    for(n=1;n<=N;n++){
    x = rand() % 100; 
    printf("%3d", x);
    
    }
    printf("\n");
    
    return 0;
}

#include <stdio.h>
#include <math.h>

void solve(double a, double b, double c);

int main(){
    double a, b, c; 
    printf("Enter a, b, c: "); 
    while(scanf("%lf%lf%lf", &a, &b, &c) != EOF){
    solve(a, b, c); 
    printf("Enter a, b, c: ");
    }
    
    return 0;
}

void solve(double a, double b, double c){
    double x1, x2; 
    double delta, real, imag; 
    
    if(a == 0) 
    printf("not quadratic equation.\n");
    else{
    delta = b*b - 4*a*c;
    if(delta >= 0) {
    x1 = (-b + sqrt(delta)) / (2*a); 
    x2 = (-b - sqrt(delta)) / (2*a);
    printf("x1 = %.2f, x2 = %.2f\n", x1, x2); 
    
    }    
    else{
    real = -b/(2*a);
    imag = sqrt(-delta) / (2*a); 
    printf("x1 = %.2f + %.2fi, x2 = %.2f - %.2fi\n", real, imag, real, imag);     
    }    
        
        
    }
    
}