A1002 A+B for Polynomials (25分)

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 N​1​​ a​N​1​​​​ N​2​​ a​N​2​​​​ ... N​K​​ a​N​K​​​​

where K is the number of nonzero terms in the polynomial, N​i​​ and a​N​i​​​​ (i=1,2,⋯,K) are the exponents and coefficients, respectively. It is given that 1≤K≤10，0≤N​K​​<⋯<N​2​​<N​1​​≤1000.

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

Solution: 

#include <cstdio>
int main() {
    double A[1001] = {0}, cof;
    int K, exp, cnt = 0;
    scanf("%d", &K);
    for (int i = 0; i < K; i++) {
        scanf("%d%lf", &exp, &cof);
        A[exp] = cof;
    }
    scanf("%d", &K);
    for (int i = 0; i < K; i++) {
        scanf("%d%lf", &exp, &cof);
        A[exp] += cof;
    }
    for (int i = 0; i < 1001; i++) {
        if (A[i] != 0) {
            cnt++;
        }
    }
    printf("%d", cnt);
    for (int i = 1000; i >= 0; i--) {
        if (A[i] != 0) {
            printf(" %d %0.1f", i, A[i]);
        }
        
    }
    return 0;
}