数组

1 原题

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}\ \dots\ 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,\dots,K) are the exponents and coefficients, respectively. It is given that 1\le K\le 10,\ 0\le N_K\lt \cdots \lt N_2 \lt N_1 \le 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

代码长度限制：16 KB
时间限制：400 ms
内存限制：64 MB
栈限制：8192 KB

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2 代码示例

Java

import java.util.ArrayList;
import java.util.List;
import java.util.Scanner;

public class Main {
    private static final int N = 1010;
    private static double[] a = new double[N];
    private static double[] b = new double[N];
    private static List<Pair> c = new ArrayList<>();

    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);

        input(scanner, a);
        input(scanner, b);

        for (int i = N - 1; i >= 0; i--) {
            if (a[i] + b[i] != 0) {
                c.add(new Pair(i, a[i] + b[i]));
            }
        }

        System.out.print(c.size());
        for (Pair pair : c) {
            System.out.printf(" %d %.1f", pair.exponent, pair.coefficient);
        }
    }

    private static void input(Scanner scanner, double[] array) {
        int n = scanner.nextInt();
        while (n-- > 0) {
            int exponent = scanner.nextInt();
            double coefficient = scanner.nextDouble();
            array[exponent] = coefficient;
        }
    }

    private static class Pair {
        int exponent;
        double coefficient;

        Pair(int exponent, double coefficient) {
            this.exponent = exponent;
            this.coefficient = coefficient;
        }
    }
}

C++

#include <iostream>
#include <cstring>
#include <algorithm>
#include <vector>

using namespace std;

const int N = 1010;

double a[N], b[N];
vector <pair<int, double>> c;    // (expon, coef)

void input(double a[]) {
    int n;
    scanf("%d", &n);
    while (n--) {
        int expon;
        double coef;
        scanf("%d%lf", &expon, &coef);
        a[expon] = coef;
    }
}

int main() {
    input(a);
    input(b);

    for (int i = N - 1; i >= 0; i--)
        if (a[i] + b[i])
            c.push_back({i, a[i] + b[i]});

    cout << c.size();
    for (auto it: c)
        printf(" %d %.1f", it.first, it.second);

    return 0;
}