1002 A+B for Polynomials （PAT甲级）

#include 
const int maxN = 1001;

int K, n, cnt;
double an;
double coef[maxN];

int main(){
    scanf("%d", &K);
    cnt = 0;
    for(int i = 0; i < K; ++i){
        scanf("%d %lf", &n, &an);
        if(an){
            cnt++;
            coef[n] = an;
        }
    }
    scanf("%d", &K);
    for(int i = 0; i < K; ++i){
        scanf("%d %lf", &n, &an);
        if(coef[n] == 0 && an){
            cnt++;
        } else if(coef[n] != 0 && coef[n] + an == 0){
            cnt--;
        }
        coef[n] += an;
    }
    printf("%d", cnt);
    for(int i = maxN - 1; i >= 0; --i){
        if(coef[i] != 0.0){
            printf(" %d %.1f", i, coef[i]);
        }
    }
    return 0;
}

题目如下：

This time, you are supposed to find A+B where A and B are two polynomials.

Input Specification:

Each input file contains one test case. Each case occupies 2 lines, and each line contains the information of a polynomial:

K N1​ aN1​​ N2​ aN2​​ ... NK​ aNK​​

where K is the number of nonzero terms in the polynomial, Ni​ and aNi​​ (i=1,2,⋯,K) are the exponents and coefficients, respectively. It is given that 1≤K≤10，0≤NK​<⋯

Output Specification:

For each test case you should output the sum of A and B in one line, with the same format as the input. Notice that there must be NO extra space at the end of each line. Please be accurate to 1 decimal place.

Sample Input:

2 1 2.4 0 3.2
2 2 1.5 1 0.5

Sample Output:

3 2 1.5 1 2.9 0 3.2