PAT structure and algorithm 7-2 univariate polynomial multiplication and addition operations (Compact line 30)

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 7-2 univariate polynomial multiplication and addition operation (20 minutes)

Design of the sum of two functions are univariate polynomial and the product.

Input formats:

Input line 2 minutes, respectively, to each row number of the polynomial given non-zero entries, then descending exponential manner enter a nonzero polynomial coefficient and the exponent (integer not exceeding the absolute value of both 1000). Between numbers separated by a space.

Output formats:

Output in 2 rows, respectively descending exponential manner, and outputs the product polynomial and polynomial coefficients and non-zero entries in the index. Between numbers separated by spaces, but the end can not have extra spaces. Zero polynomial should be output 0 0.

Sample input:

4 3 4 -5 2  6 1  -2 0
3 5 20  -7 4  3 1

Sample output:

15 24 -25 22 30 21 -10 20 -21 8 35 6 -33 5 14 4 -15 3 18 2 -6 1
5 20 -4 4 -5 2 9 1 -2 0

#include<iostream>
#include <map>
using namespace std;
void input(map<int, int, greater<int>>& mp) {
	int t, e, n;
	cin >> n;
	for (int i = 0; i < n; ++i) {
		cin >> t >> e;
		mp[e] = t;
	}
}
void output(const map<int, int, greater<int>>& mp) {
	bool flag = false;
	for (auto& it : mp) {
		if (it.second) {
			cout << (flag ? " " : "") << it.second << " " << it.first ;
			flag = true;
		}
	}
	cout << (flag ? "" : "0 0") << endl;
}
int main(){
	map<int, int,greater<int>> a, b, add, mult;
	int n,  flag = 0;
	input(a); input(b);
	add = a;
	for (auto& it : b) 
		add[it.first] += it.second;
	for (auto& i : a) {
		for (auto& j : b) {
			mult[i.first + j.first] += i.second * j.second;
		}
	}
	output(mult); output(add);
	return 0;
}