Java 带链表的多项式乘法次数数学错误
我的乘法逻辑不正确。当我必须把两个多项式相乘得到的相同程度的项相加时,我似乎没有考虑Java 带链表的多项式乘法次数数学错误,java,loops,math,linked-list,logic,Java,Loops,Math,Linked List,Logic,我的乘法逻辑不正确。当我必须把两个多项式相乘得到的相同程度的项相加时,我似乎没有考虑 public Polynomial multiply(Polynomial p) { if (p.poly == null || this.poly == null) { Polynomial zero = new Polynomial(); zero.poly = new Node (0, 0, null); return zero; } els
public Polynomial multiply(Polynomial p) {
if (p.poly == null || this.poly == null) {
Polynomial zero = new Polynomial();
zero.poly = new Node (0, 0, null);
return zero;
} else {
Polynomial retPol = new Polynomial();
retPol.poly = new Node(0, 0, null);
Node front = retPol.poly;
Node entered = p.poly;
Node thisPol = this.poly;
int high = Integer.MIN_VALUE;
int low = Integer.MAX_VALUE;
while (entered != null) {
thisPol = this.poly;
while (thisPol != null) {
if (thisPol.term.degree + entered.term.degree > high)
high = thisPol.term.degree + entered.term.degree;
if (thisPol.term.degree + entered.term.degree < low)
low = thisPol.term.degree + entered.term.degree;
thisPol = thisPol.next;
}
entered = entered.next;
}
entered = p.poly;
Node create = front;
for (int i = low; i <= high; i++) {
create.term.degree = i;
create.term.coeff = 0;
create.next = new Node (0, 0, null);
create = create.next;
}
entered = p.poly;
while (entered != null) {
thisPol = this.poly;
while (thisPol != null) {
int degree = entered.term.degree + thisPol.term.degree;
create = front;
while (create != null) {
if (create.term.degree == degree) {
create.term.coeff = entered.term.coeff * thisPol.term.coeff;
}
create = create.next;
}
thisPol = thisPol.next;
}
entered = entered.next;
}
create = front;
while (create != null) {
if (create.term.degree == high) {
create.next = null;
create = create.next;
}
else
create = create.next;
}
retPol.poly = front;
return retPol;
}
}
公共多项式乘法(多项式p){
if(p.poly==null | | this.poly==null){
多项式零=新多项式();
zero.poly=新节点(0,0,null);
返回零;
}否则{
多项式retPol=新多项式();
retPol.poly=新节点(0,0,null);
节点前端=retPol.poly;
输入的节点=p.poly;
节点thisPol=this.poly;
int高=整数最小值;
int low=整数最大值;
while(输入!=null){
thisPol=this.poly;
while(thisPol!=null){
如果(thisPol.term.degree+entered.term.degree>高)
高=此pol.term.degree+输入的.term.degree;
如果(thisPol.term.degree+entered.term.degree<低)
低=此pol.term.degree+输入的.term.degree;
thisPol=thisPol.next;
}
entered=entered.next;
}
输入=p.poly;
节点创建=前端;
对于(int i=low;i我认为您应该总结所有对,而不是在这里选择最后一对(或随机):
if (create.term.degree == degree) {
create.term.coeff += entered.term.coeff * thisPol.term.coeff;
}
[更新]您的代码和我的更正对我非常有效:
public class PolynomialTest {
public static void main(String[] args) {
// 4x^5 - 2x^3 + 2x + 3
Polynomial p1 = new Polynomial(new Node(4.0, 5, new Node(-2.0, 3, new Node(2.0, 1, new Node(3.0, 0, null)))));
// 8x^4 + 4x^3 - 3x + 9
Polynomial p2 = new Polynomial(new Node(8.0, 4, new Node(4.0, 3, new Node(-3.0, 1, new Node(9.0, 0, null)))));
Polynomial p3 = p1.multiply(p2);
System.out.println(p3.toString());
}
}
class Term {
int degree;
double coeff;
}
class Node {
Term term;
Node next;
public Node(double coeff, int degree, Node next) {
this.term = new Term();
this.term.degree = degree;
this.term.coeff = coeff;
this.next = next;
}
}
class Polynomial {
private Node poly;
public Polynomial() {}
public Polynomial(Node poly) {
this.poly = poly;
}
public Polynomial multiply(Polynomial p) {
if (p.poly == null || this.poly == null) {
Polynomial zero = new Polynomial();
zero.poly = new Node (0, 0, null);
return zero;
} else {
Polynomial retPol = new Polynomial();
retPol.poly = new Node(0, 0, null);
Node front = retPol.poly;
Node entered = p.poly;
Node thisPol = this.poly;
int high = Integer.MIN_VALUE;
int low = Integer.MAX_VALUE;
while (entered != null) {
thisPol = this.poly;
while (thisPol != null) {
if (thisPol.term.degree + entered.term.degree > high)
high = thisPol.term.degree + entered.term.degree;
if (thisPol.term.degree + entered.term.degree < low)
low = thisPol.term.degree + entered.term.degree;
thisPol = thisPol.next;
}
entered = entered.next;
}
entered = p.poly;
Node create = front;
for (int i = low; i <= high; i++) {
create.term.degree = i;
create.term.coeff = 0;
create.next = new Node (0, 0, null);
create = create.next;
}
entered = p.poly;
while (entered != null) {
thisPol = this.poly;
while (thisPol != null) {
int degree = entered.term.degree + thisPol.term.degree;
create = front;
while (create != null) {
if (create.term.degree == degree) {
create.term.coeff += entered.term.coeff * thisPol.term.coeff;
}
create = create.next;
}
thisPol = thisPol.next;
}
entered = entered.next;
}
create = front;
while (create != null) {
if (create.term.degree == high) {
create.next = null;
create = create.next;
}
else
create = create.next;
}
retPol.poly = front;
return retPol;
}
}
@Override
public String toString() {
StringBuilder sb = new StringBuilder();
Node n = poly;
while (n != null) {
if (sb.length() > 0)
sb.append(" + ");
sb.append(n.term.coeff);
if (n.term.degree > 0)
sb.append("x");
if (n.term.degree > 1)
sb.append("^").append(n.term.degree);
n = n.next;
}
return sb.toString();
}
}
我认为您应该总结所有对,而不是在这里选择最后(或随机)对:
if (create.term.degree == degree) {
create.term.coeff += entered.term.coeff * thisPol.term.coeff;
}
[更新]您的代码和我的更正对我非常有效:
public class PolynomialTest {
public static void main(String[] args) {
// 4x^5 - 2x^3 + 2x + 3
Polynomial p1 = new Polynomial(new Node(4.0, 5, new Node(-2.0, 3, new Node(2.0, 1, new Node(3.0, 0, null)))));
// 8x^4 + 4x^3 - 3x + 9
Polynomial p2 = new Polynomial(new Node(8.0, 4, new Node(4.0, 3, new Node(-3.0, 1, new Node(9.0, 0, null)))));
Polynomial p3 = p1.multiply(p2);
System.out.println(p3.toString());
}
}
class Term {
int degree;
double coeff;
}
class Node {
Term term;
Node next;
public Node(double coeff, int degree, Node next) {
this.term = new Term();
this.term.degree = degree;
this.term.coeff = coeff;
this.next = next;
}
}
class Polynomial {
private Node poly;
public Polynomial() {}
public Polynomial(Node poly) {
this.poly = poly;
}
public Polynomial multiply(Polynomial p) {
if (p.poly == null || this.poly == null) {
Polynomial zero = new Polynomial();
zero.poly = new Node (0, 0, null);
return zero;
} else {
Polynomial retPol = new Polynomial();
retPol.poly = new Node(0, 0, null);
Node front = retPol.poly;
Node entered = p.poly;
Node thisPol = this.poly;
int high = Integer.MIN_VALUE;
int low = Integer.MAX_VALUE;
while (entered != null) {
thisPol = this.poly;
while (thisPol != null) {
if (thisPol.term.degree + entered.term.degree > high)
high = thisPol.term.degree + entered.term.degree;
if (thisPol.term.degree + entered.term.degree < low)
low = thisPol.term.degree + entered.term.degree;
thisPol = thisPol.next;
}
entered = entered.next;
}
entered = p.poly;
Node create = front;
for (int i = low; i <= high; i++) {
create.term.degree = i;
create.term.coeff = 0;
create.next = new Node (0, 0, null);
create = create.next;
}
entered = p.poly;
while (entered != null) {
thisPol = this.poly;
while (thisPol != null) {
int degree = entered.term.degree + thisPol.term.degree;
create = front;
while (create != null) {
if (create.term.degree == degree) {
create.term.coeff += entered.term.coeff * thisPol.term.coeff;
}
create = create.next;
}
thisPol = thisPol.next;
}
entered = entered.next;
}
create = front;
while (create != null) {
if (create.term.degree == high) {
create.next = null;
create = create.next;
}
else
create = create.next;
}
retPol.poly = front;
return retPol;
}
}
@Override
public String toString() {
StringBuilder sb = new StringBuilder();
Node n = poly;
while (n != null) {
if (sb.length() > 0)
sb.append(" + ");
sb.append(n.term.coeff);
if (n.term.degree > 0)
sb.append("x");
if (n.term.degree > 1)
sb.append("^").append(n.term.degree);
n = n.next;
}
return sb.toString();
}
}
你说不走运是什么意思?错误的数字?你想乘法的多项式是什么?你只显示了预期的结果多项式,没有输入。哎呀,对不起。[4x^5-2x^3+2x+3]*[8x^4+4x^3-3x+9]
@qqxx,我刚刚检查过,一切似乎都很好。请参阅我的更新以获取完整的示例。你所说的不走运是什么意思?错误的数字?你想乘法的多项式是什么?你只显示了预期的结果多项式,没有输入。哎呀,对不起。[4x^5-2x^3+2x+3]*[8x^4+4x^3-3x+9]
@qqxx,我刚刚检查过,一切似乎都很好。请参阅我的更新以获取完整示例。