95 lines
2.3 KiB
C
95 lines
2.3 KiB
C
#include <stdio.h>
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#include <stdlib.h>
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#include <math.h>
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void count_root(int arrR[], int arrL[], int ans[], int countF, int countL, int *len_ans) {
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int i, j, k = 0;
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for (i = 0; i < countF; i++) {
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for (j = 0; j < countL; j++) {
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if (arrL[j] != 0 && arrR[i] != 0 && arrL[j] % arrR[i] == 0) {
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ans[k++] = arrL[j] / arrR[i];
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}
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}
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}
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*len_ans = k;
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}
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void plus_root_negative(int arr[], int *len) {
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int i, new_len = *len * 2;
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for (i = 0; i < *len; i++) {
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arr[*len + i] = -arr[i];
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}
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*len = new_len;
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}
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void find_factor(int num, int fac[], int *count) {
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int i, j = 0;
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for (i = 1; i <= sqrt(abs(num)); i++) {
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if (num % i == 0) {
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fac[j++] = i;
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if (i != num / i) {
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fac[j++] = num / i;
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}
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}
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}
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*count = j;
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}
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double evaluate_polynomial(int A[], int len, double x) {
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double result = 0;
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int i;
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for (i = 0; i < len; i += 2) {
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result += A[i] * pow(x, A[i+1]);
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}
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return result;
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}
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void Substitute(int len_root, int arr[], int ans[], int A[], int len_A, int *len_ans) {
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int i, j = 0;
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double result;
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for (i = 0; i < len_root; i++) {
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result = evaluate_polynomial(A, len_A, arr[i]);
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if (fabs(result) < 1e-10) { // 使用小的閾值來處理浮點誤差
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ans[j++] = arr[i];
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}
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}
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*len_ans = j;
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}
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int main() {
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int i, len, countF, countL, len_root = 0, len_ans = 0;
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int A[] = { 2, 2, 1, 0, -100}; // x^3 - 2x^2 - x + 2
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int facF[100], facL[100], root[200], ans[100];
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len = sizeof(A) / sizeof(A[0]);
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find_factor(abs(A[0]), facF, &countF);
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find_factor(abs(A[len-2]), facL, &countL);
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printf("最高次方項因數為: ");
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for (i = 0; i < countF; i++) {
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printf("%d ", facF[i]);
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}
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printf("\n常數項因數為: ");
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for (i = 0; i < countL; i++) {
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printf("%d ", facL[i]);
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}
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printf("\n");
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count_root(facF, facL, root, countF, countL, &len_root);
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plus_root_negative(root, &len_root);
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printf("可能的根：\n");
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for (i = 0; i < len_root; i++) {
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printf("root[%d] = %d\n", i, root[i]);
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}
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Substitute(len_root, root, ans, A, len, &len_ans);
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printf("多項式的根：\n");
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for (i = 0; i < len_ans; i++) {
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printf("x = %d\n", ans[i]);
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}
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return 0;
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}
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