编程实现一元多项式的加法运算。第一个一元多项式A;第二个多项式B。以(0，0作为输入结束)C语言

以下是一元多项式的加法运算的C语言代码实现：

#include <stdio.h>
#include <stdlib.h>

/* 定义多项式的结构体 */
typedef struct PolyNode *Polynomial;
struct PolyNode {
    int coef; /* 系数 */
    int expon; /* 指数 */
    Polynomial next; /* 指向下一项的指针 */
};

/* 多项式加法运算 */
Polynomial PolyAdd(Polynomial A, Polynomial B) {
    Polynomial head, tail, temp;
    head = (Polynomial) malloc(sizeof(struct PolyNode));
    tail = head;
    while (A && B) { /* A和B都非空 */
        if (A->expon == B->expon) { /* 次数相等 */
            int sum = A->coef + B->coef;
            if (sum != 0) { /* 系数和不为0 */
                temp = (Polynomial) malloc(sizeof(struct PolyNode));
                temp->coef = sum;
                temp->expon = A->expon;
                tail->next = temp;
                tail = temp;
            }
            A = A->next;
            B = B->next;
        } else if (A->expon > B->expon) { /* A的次数大于B的次数 */
            temp = (Polynomial) malloc(sizeof(struct PolyNode));
            temp->coef = A->coef;
            temp->expon = A->expon;
            tail->next = temp;
            tail = temp;
            A = A->next;
        } else { /* A的次数小于B的次数 */
            temp = (Polynomial) malloc(sizeof(struct PolyNode));
            temp->coef = B->coef;
            temp->expon = B->expon;
            tail->next = temp;
            tail = temp;
            B = B->next;
        }
    }
    /* 将剩余的项添加到结果多项式中 */
    for (; A; A = A->next) {
        temp = (Polynomial) malloc(sizeof(struct PolyNode));
        temp->coef = A->coef;
        temp->expon = A->expon;
        tail->next = temp;
        tail = temp;
    }
    for (; B; B = B->next) {
        temp = (Polynomial) malloc(sizeof(struct PolyNode));
        temp->coef = B->coef;
        temp->expon = B->expon;
        tail->next = temp;
        tail = temp;
    }
    tail->next = NULL;
    temp = head;
    head = head->next;
    free(temp); /* 释放头结点 */
    return head;
}

/* 多项式读入 */
Polynomial ReadPoly() {
    Polynomial head, tail, temp;
    int n, c, e;
    head = (Polynomial) malloc(sizeof(struct PolyNode));
    head->next = NULL;
    tail = head;
    scanf("%d", &n); /* 读入项数 */
    while (n--) {
        scanf("%d %d", &c, &e);
        temp = (Polynomial) malloc(sizeof(struct PolyNode));
        temp->coef = c;
        temp->expon = e;
        tail->next = temp;
        tail = temp;
    }
    tail->next = NULL;
    temp = head;
    head = head->next;
    free(temp); /* 释放头结点 */
    return head;
}

/* 多项式输出 */
void PrintPoly(Polynomial P) {
    if (!P) {
        printf("0 0\n");
        return;
    }
    printf("%d %d", P->coef, P->expon);
    P = P->next;
    while (P) {
        printf(" %d %d", P->coef, P->expon);
        P = P->next;
    }
    printf("\n");
}

/* 主函数 */
int main() {
    Polynomial A, B, C;
    A = ReadPoly();
    B = ReadPoly();
    C = PolyAdd(A, B);
    PrintPoly(C);
    return 0;
}

其中，`PolyNode` 结构体表示一项多项式，`Polynomial` 则是指向 `PolyNode` 的指针类型。`PolyAdd` 函数实现了多项式的加法运算，`ReadPoly` 函数实现了多项式的读入，`PrintPoly` 函数实现了多项式的输出。在主函数中，先读入两个多项式，然后调用 `PolyAdd` 函数将它们相加，最后输出结果多项式。