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题目

This time, you are supposed to find where and 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:

...

where is the number of nonzero terms in the polynomial, and
( ) are the exponents and coefficients,
respectively. It is given that , .

Output Specification:

For each test case you should output the product of and 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 up to 1 decimal place.

Sample Input:

2 1 2.4 0 3.2
2 2 1.5 1 0.5

Sample Output:

3 3 3.6 2 6.0 1 1.6

思路

为了思路简单，就直接开大数组遍历了，没有什么难点

代码

最新代码@github，欢迎交流

#include <stdio.h>
int main()
{
    int N, exp, count = 0;
    float coef, A[1001] = {0}, B[1001] = {0}, MUL[2001] = {0};

    scanf("%d", &N);
    while(N--){ scanf("%d %f", &exp, &coef); A[exp] = coef; }
    scanf("%d", &N);
    while(N--){ scanf("%d %f", &exp, &coef); B[exp] = coef; }

    for(int i = 0; i < 1001; i++)
        for(int j = 0; j < 1001; j++)
            MUL[i + j] += A[i] * B[j];

    for(int i = 0; i < 2001; i++)
        if(MUL[i]) count++;

    printf("%d", count);
    for(int i = 2000; i >= 0; i--) if(MUL[i])
        printf(" %d %.1f", i, MUL[i]);

    return 0;
}