. Here is the Horner's rule-Code: Select all
a_nx^n+a_(n-1)x^(n-1)+...+a_0=((a_nx+a_(n-1))x+...)x+a_0. 
) pow() function is responsible for this.Code: Select all
#include<cstdio>
#include<cstdlib>
#include<cmath>
#include<cstring>
#include<iostream>
#include<algorithm>
#include<string>
#include<sstream>
using namespace std;
int arr[100000000];
main()
{
string strx,str;
while(getline(cin, strx))
{
stringstream ss(strx);
long long int x;
ss>>x;
getline(cin, str);
stringstream in(str);
int n = 0;
while(in >> arr[n])
n++;
long long int poly = 0;
for(int i = 0;i<n ; i++)
poly = poly + (n-i-1)*arr[i]*pow(x,n-i-2.0);
printf("%lld\n", poly);
}
}
Code: Select all
#include<cstdio>
#include<cstdlib>
#include<cmath>
#include<cstring>
#include<iostream>
#include<algorithm>
#include<string>
#include<sstream>
using namespace std;
int arr[100000000];
long long int power(long long int x, long long int n)
{
if(n == 1)
return x;
else if(n == 0)
return 1;
else if(n&1)
return power(x,n/2)*power(x,n/2+1);
else
return power(x,n/2)*power(x,n/2);
}
main()
{
string strx,str;
while(getline(cin, strx))
{
stringstream ss(strx);
long long int x;
ss>>x;
getline(cin, str);
stringstream in(str);
int n = 0;
while(in >> arr[n])
n++;
long long int poly = 0;
for(int i = 0;i<n ; i++)
poly = poly + (n-i-1)*arr[i]*power(x,n-i-2);
printf("%lld\n", poly);
}
}