多项式

//简单的一维数组，适合稠密多项式 
#include <stdio.h>
#include <stdlib.h>
#define MaxDegree 1000
typedef struct {
    int CoeffArray[MaxDegree+1];
    int HighPower;
} *Polynomial;

void ZeroPolynomial(Polynomial poly)
{
    for (int i = 0; i <= MaxDegree; ++i) {
        poly->CoeffArray[i] = 0;
    }
    poly->HighPower = 0;
}

int Max(int a, int b)
{
    return a > b ? a : b;
}
//多项式相加 
void AddPolynomial(const Polynomial Poly1, const Polynomial Poly2, Polynomial PolySum)
{
    ZeroPolynomial(PolySum);
    PolySum->HighPower = Max(Poly1->HighPower, Poly2->HighPower);
    
    for (int i =  PolySum->HighPower; i >= 0; --i) {
        PolySum->CoeffArray[i] = Poly1->CoeffArray[i] + Poly2->CoeffArray[i];
    }
}
//多项式相乘 
void MultPolynomial(const Polynomial Poly1, const Polynomial Poly2, Polynomial PolyProd) 
{
    ZeroPolynomial(PolyProd);
    PolyProd->HighPower = Poly1->HighPower + Poly2->HighPower;
    
    if (PolyProd->HighPower > MaxDegree)
        exit(1);
    else
        for (int i = 0; i <= Poly1->HighPower; ++i)
            for (int j = 0; j <= Poly2->HighPower; ++j)
            PolyProd->CoeffArray[i+j] += Poly1->CoeffArray[i] * Poly2->CoeffArray[j];
}