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 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 Specification:
For each test case you should output the product 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 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
参考代码:
#include<iostream>
#include<vector>
#include<cstdio>
using namespace std;
int main()
{
vector<int>v;
vector<double>v1(1002), v2(2005);
int n1, n2, exp, cnt = 0;
double coef;
cin >> n1;
for (int i = 1; i <= n1; i++)
{
cin >> exp >> coef;
v1[exp] = coef;
v.push_back(exp);
}
cin >> n2;
for (int i = 1; i <= n2; i++)
{
//指数,系数
cin >> exp >> coef;
for (auto val : v)
{
v2[exp + val] += v1[val]*coef;
}
}
for (auto val : v2)
{
if (val != 0)
cnt++;
}
cout << cnt;
for (int j=v2.size()-1;j>=0;j--)
{
if (v2[j] != 0)
printf(" %d %.1f", j, v2[j]);
}
return 0;
}