1002. A+B for Polynomials (25)（PAT甲级）

Problem Description

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

多项式的加法，

#include <iostream>
#include <cstdio>
using namespace std;
double ans[1005];
int main() {
	int k1, k2, n;
	double a;
	scanf("%d", &k1);
	for(int i = 0; i < k1; i++) {
		scanf("%d %lf", &n, &a);
		ans[n] += a;
	}
	scanf("%d", &k2);
	for(int i = 0; i < k2; i++) {
		scanf("%d %lf", &n, &a);
		ans[n] += a;
	}	
	int cnt = 0;
	for(int i = 0; i <= 1000; i++) {
		if(ans[i] != 0) {
			cnt++;
		}
	}
	printf("%d", cnt);
	for(int i = 1001; i >= 0; i--) {
		if(ans[i] != 0) {
			printf(" %d %.1lf", i, ans[i]);
		}
	}
	return 0;
}