title
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
solution
#include<stdio.h>
#include<string>
#include<iostream>
#include<unordered_map>
#include<algorithm>
#include<utility>
#include<functional>
#include<queue>
#include<sstream>
using namespace std;
#define N 2001
#define inf 99999
double a[N], b[N], ans[N];
int main() {
int n;
cin >> n;
int t;
for (int i = 0; i < n; i++) {
scanf("%d", &t);
scanf("%lf", &a[t]);
}
cin >> n;
for (int i = 0; i < n; i++) {
scanf("%d", &t);
scanf("%lf", &b[t]);
for (int j = 0; j < 1001; j++) {
ans[t + j] += b[t] * a[j];
}
}
int num = 0;
for (int i = 2000; i >= 0; i--) {
if (ans[i] != 0.0) {
num++;
}
}
cout << num;
for (int i = 2000; i >= 0; i--) {
if (ans[i] != 0.0) {
printf(" %d %.1f", i, ans[i]);
}
}
return 0;
}