数据结构 02-线性结构2 一元多项式的乘法与加法运算 (20 分)

#include <iostream>
#include <vector>
#include <algorithm>
#include <map>
using namespace std;
void getPolynomialNumber(map<int,int> &po,int n){
    po.clear();
    int e;
    int num;
    for(int i=0;i<n;i++){
        cin >> num >> e;
        po[e]=num;
    }
}
void addPoly(map<int,int> &p1,map<int,int> &result){
    map<int,int>::iterator it;
    for(it=p1.begin();it!=p1.end();it++){
        result[it->first]+=it->second;
        if(result[it->first]==0){
            map<int,int>::iterator searchIt;
            searchIt=result.find(it->first);
            result.erase(searchIt);
        }
    }
}
void multiplyPoly(map<int,int> &p1,map<int,int> &p2,map<int,int> &result){
    
    map<int,int>::iterator it1;
    map<int,int>::iterator it2;
    for(it1=p1.begin();it1!=p1.end();it1++){
        for(it2=p2.begin();it2!=p2.end();it2++){
            result[it1->first+it2->first]+=it1->second*it2->second;
            if(result[it1->first+it2->first]==0){
                map<int,int>::iterator searchIt;
                searchIt=result.find(it1->first+it2->first);
                result.erase(searchIt);
            }
        }
    }
//    return result;
}
void printPoly(map<int,int> &p){
    vector<int> e;
    vector<int> n;
    map<int,int>::iterator it;
    for(it=p.begin();it!=p.end();it++){
        e.push_back(it->first);
        n.push_back(it->second);
    }
    if(e.size()==0){
        cout << "0 0"<<endl;
    }else{
        cout <<n[n.size()-1] <<" "<<e[e.size()-1] ;
        for(int i=e.size()-2;i>=0;i--){
            cout <<" "<<n[i] <<" "<<e[i];
        }
        cout <<endl;
    }
}
int main(){
    map<int,int> p1;
    map<int,int> p2;
    map<int,int> result1;
    map<int,int> result2;
    int n,m;
    cin >> n;
    getPolynomialNumber(p1, n);
    cin >> m;
    getPolynomialNumber(p2, m);
    addPoly(p1, result1);
    addPoly(p2, result1);
    multiplyPoly(p1, p2,result2);
    printPoly(result2);
    printPoly(result1);
    return 0;
}