61 lines
1.5 KiB
C
61 lines
1.5 KiB
C
#include <stdio.h>
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#include <stdlib.h>
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#include <math.h>
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void display_pol(double* coef, size_t degree) {
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if (coef == NULL) {
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printf("NULL\n");
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return;
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}
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for (size_t i = 0; i <= degree; i++) {
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printf("%lf", coef[i]);
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if (i < degree) {
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printf(" * x^%lu + ", degree - i);
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}
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}
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printf("\n");
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}
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double compute_pol(double* coef, size_t degree, double x) {
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if (coef == NULL) {
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return 0;
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}
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double result = 0;
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for (size_t i = 0; i <= degree; i++) {
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result += coef[i] * pow(x, degree - i);
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}
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return result;
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}
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unsigned int get_real_roots(double* coef, size_t degree, double* root_1, double* root_2) {
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if (coef == NULL || root_1 == NULL || root_2 == NULL || degree != 2 || coef[0] == 0) {
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return 0;
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}
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double delta = pow(coef[1], 2) - 4 * coef[0] * coef[2];
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if (delta < 0) {
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*root_1 = 0;
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*root_2 = 0;
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return 0;
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}
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*root_1 = (-coef[1] - sqrt(delta)) / (2 * coef[0]);
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*root_2 = (-coef[1] + sqrt(delta)) / (2 * coef[0]);
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if (delta == 0) {
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return 1;
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}
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return 2;
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}
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int main() {
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double coef[] = {1, 2, 1};
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size_t degree = 2;
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double x = 1;
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double root_1 = 0;
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double root_2 = 0;
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printf("Polynomial: ");
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display_pol(coef, degree);
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printf("f(%lf) = %lf\n", x, compute_pol(coef, degree, x));
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printf("Number of real roots: %u\n", get_real_roots(coef, degree, &root_1, &root_2));
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printf("Roots: %lf, %lf\n", root_1, root_2);
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return 0;
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}
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