1009 Product of Polynomials (25 分)
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 aN1 N2 aN2 ... NK aNK
where K is the number of nonzero terms in the polynomial, Ni and aNi (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
简单的多项式相乘然后输出非零项
#include<bits/stdc++.h>
using namespace std;
int main()
{
int a,b;
cin>>a;
double dat[1111];
double datt[1111];
double ans[2111];
memset(dat,0,sizeof(dat));
memset(datt,0,sizeof(datt));
memset(ans,0,sizeof(ans));
double x;
int s;
for(int i=0;i<a;i++)
{
cin>>s>>x;
dat[s]=x;
}
cin>>b;
for(int i=0;i<b;i++)
{
cin>>s>>x;
datt[s]=x;
}
for(int i=0;i<=1000;i++)
{
for(int j=0;j<=1000;j++)
{
ans[i+j]+=dat[i]*datt[j];
}
}
int js=0;
for(int i=0;i<=2000;i++)
if(ans[i]!=0)js++;
cout<<js;
for(int i=2000;i>=0;i--)
{
if(ans[i]!=0)
{
cout<<" "<<i<<" ";
printf("%.1lf",ans[i]);
}
}
cout<<endl;
return 0;
}