甲级Test1002

1002. A+B for Polynomials (25）

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

Input

Each input file contains one test case. Each case occupies 2 lines, and each line contains the information of a polynomial:K N1 a_N1 N2 a_N2 ... NK a_NK, where K is the number of nonzero terms in the polynomial, Ni and a_Ni (i=1, 2, ..., K) are the exponents and coefficients, respectively. It is given that 1 <= K <= 10，0 <= NK < ... < N2 < N1 <=1000.

Output

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

难点分析：

1.相加系数为0的情况。

2.避免打印多余的空格。

3.系数要求输出保留一位小数。

代码（以下代码仅负责实现，暂未考虑优化）：

#include 
#include "iomanip"
#include
using namespace std;

int main() {
    map<int, double> poly1;
    map<int, double> poly2;
    map<int, double, greater<int>> poly3;

//读入map集合
    int n = 0;
    cin >> n;
    for (; n > 0; n--) {
        int e = 0;
        double p = 0;
        cin >> e >> p;
        double temp = poly1[e]+p;
        poly1[e] = temp;
    }

    cin >> n;
    for (; n > 0; n--) {
        int e = 0;
        double p = 0;
        cin >> e >> p;
        double temp = poly2[e]+p;
        poly2[e] = temp;
    }
//做加法
    map<int, double>::iterator iterator1 = poly1.begin();
    map<int, double>::iterator iterator2 = poly2.begin();

    while (iterator1 != poly1.end() && iterator2 != poly2.end()) {
        int poly1E = iterator1->first;
        double poly1P = iterator1->second;
        int poly2E = iterator2->first;
        double poly2P = iterator2->second;

        if (poly1E < poly2E) {
            poly3.insert(map<int, double>::value_type(poly1E, poly1P));
            iterator1++;
        } else if (poly1E > poly2E) {
            poly3.insert(map<int, double>::value_type(poly2E, poly2P));
            iterator2++;
        } else if (poly1E == poly2E) {
            if (poly1P + poly2P != 0) {
                poly3.insert(map<int, double>::value_type(poly2E, poly2P + poly1P));
            }
            iterator1++;
            iterator2++;
        }
    }

    if (iterator1 == poly1.end()) {
        while (iterator2 != poly2.end()) {
            poly3.insert(map<int, double>::value_type(iterator2->first, iterator2->second));
            iterator2++;
        }
    } else if (iterator2 == poly2.end()) {
        while (iterator1 != poly1.end()) {
            poly3.insert(map<int, double>::value_type(iterator1->first, iterator1->second));
            iterator1++;
        }
    }


//输出结果
    cout << poly3.size();
    cout<<setiosflags(ios::fixed);
    cout.precision(1);
    for (map<int, double>::iterator iterator3 = poly3.begin(); iterator3 != poly3.end(); iterator3++) {
        double a = iterator3->second ;
        cout << " " << iterator3->first << " " << a;
    }


    return 0;
}