Design functions to find the product and sum of two one-variable polynomials respectively.
Input format:
The input is divided into 2 lines. Each line first gives the number of non-zero terms of the polynomial, and then enters the coefficient and exponent of a polynomial non-zero term in an exponential descending manner (the absolute values are all integers not exceeding 1000). Separate numbers with spaces.
Output format:
The output is divided into 2 lines, and the coefficients and exponents of the product polynomial and the non-zero terms of the sum polynomial are output in an exponential descending manner. Numbers should be separated by spaces, but there should be no extra spaces at the end. A zero polynomial should be output 0 0.
Input example:
4 3 4 -5 2 6 1 -2 0
3 5 20 -7 4 3 1
Output sample:
15 24 -25 22 30 21 -10 20 -21 8 35 6 -33 5 14 4 -15 3 18 2 -6 1
5 20 -4 4 -5 2 9 1 -2 0Let’s start with a wrong version...the first time I did it, I didn’t take a lot of it into account.
#include<iostream>
using namespace std;
struct node{
int a;
int n;
};
int main(){
int x[1001];
int N1,N2;
int i,k;
int flag1=0,flag2=0;
// node ttt;
// vector<node>x3;
cin>>N1;
node x1[N1];
for(i=0;i<1001;i++){
x[i]=0;
}
for(i=0;i<N1;i++){
cin>>x1[i].a>>x1[i].n;
}
cin>>N2;
node x2[N2];
for(i=0;i<N2;i++){
cin>>x2[i].a>>x2[i].n;
}
for(k=0;k<N2;k++){
for(i=0;i<N1;i++){
//if(i==N1-1&&k==N2-1) cout<<x2[k].a*x1[i].a<<" "<<x2[k].n+x1[i].n;
//else cout<<x2[k].a*x1[i].a<<" "<<x2[k].n+x1[i].n<<" ";
x[x2[k].n+x1[i].n]+=x2[k].a*x1[i].a;
}
}
int t=-1;
for(i=0;i<1001;i++){
if(x[i]!=0){
t = i;
break;
}
}
if(i==1001) flag1=1;
for(i=1000;i>=0;i--){
if(x[i]!=0){
if(i!=t){
cout<<x[i]<<" "<<i<<" ";
}
else cout<<x[i]<<" "<<i;
}
if(flag1==1){
cout<<"0 0";
}
}
cout<<endl;
i=0;
k=0;
// int flag1=0,flag2=0;
while(i<N1||k<N2){
if(i==N1||k==N2){
if(i==N1){
if(k==N2-1){
cout<<x2[k].a<<" "<<x2[k].n;
k++;
}
else{
cout<<x2[k].a<<" "<<x2[k].n<<" ";
k++;
}
}
else if(k==N2){
if(i==N1-1){
cout<<x1[i].a<<" "<<x1[i].n;
i++;
}
else{
cout<<x1[i].a<<" "<<x1[i].n<<" ";
i++;
}
}
}
else if(x1[i].n==x2[k].n){
if(i==N1-1&&k==N2-1){
cout<<x1[i].a+x2[k].a<<" "<<x1[i].n;
i++;
k++;
}
else {
cout<<x1[i].a+x2[k].a<<" "<<x1[i].n<<" ";
i++;
k++;
}
}
else if(x1[i].n>x2[k].n){
cout<<x1[i].a<<" "<<x1[i].n<<" ";
i++;
}
else if(x1[i].n<x2[k].n){
cout<<x2[k].a<<" "<<x2[k].n<<" ";
k++;
}
}
return 0;
}Later, I mainly made a new one with reference to https://www.cnblogs.com/yuxiaoba/p/8326018.html .
This question mainly needs to consider the tips of outputting 0 0 when zero polynomial is used, and not adding spaces at the end.
if(s[i]){
if(cnt){
cout<<" ";
}
cout<<s[i]<<" "<<i;
cnt++;
}#include<iostream>
using namespace std;
#define N 2002
int x1[N]={0},x2[N]={0},m[N]={0},s[N]={0};
int main(){
int i,t1,t2,k;
int T;
int cnt;
cin>>T;
for(i=0;i<T;i++){
cin>>t1>>t2;
x1[t2]+=t1;
}
// cout<<"1*"<<endl;
cin>>T;
for(i=0;i<T;i++){
cin>>t1>>t2;
x2[t2]+=t1;
}
// cout<<"1*"<<endl;
for(i=0;i<N;i++){
if(x1[i]){
for(k=0;k<N;k++){
if(x2[k]){
m[i+k]+=x1[i]*x2[k];
}
}
}
}
for(i=N;i>=0;i--){
if(m[i]){
if(cnt){
cout<<" ";
}
cout<<m[i]<<" "<<i;
cnt++;
}
}
if(!cnt){
cout<<"0 0";
}
cout<<endl;
for(i=0;i<N;i++){
if(x1[i]){
s[i]+=x1[i];
}
if(x2[i]){
s[i]+=x2[i];
}
}
cnt=0;
for(i=N;i>=0;i--){
if(s[i]){
if(cnt){
cout<<" ";
}
cout<<s[i]<<" "<<i;
cnt++;
}
}
if(!cnt){
cout<<"0 0";
}
return 0;
}