Please help!! what am I doing wrong ? The power function is working fine but still getting wrong answer See this
Thanks bro. It worked. Maybe I was missing some mod operation in my main code. I will check it out.
hello geeks,
Please have a look on my code, I am getting segmentation fault.
#include
#include <bits/stdc++.h>
#include
#include
using namespace std;
#define ll long long int
#define mod 1e9+7
ll fxp(ll a,ll b,ll m)
{
if(b==2)
return (aa)%m;
if(b%2==0)
return fmod(fxp(aa,b/2,m),mod);
return fmod(fxp(a,b-1,m)*a,mod);
}
void swap(ll &a,ll &b){ ll t=a; a=b; b=t;}
int main() {
// your code goes here
int t;
cin>>t;
while(t–)
{
ll n,A,s,res=0;
cin>>n>>A;
for(ll i=1;i<=n;i++)
{
s=fxp(A,2i-1,mod);
A=As;
res+=s;
res=fmod(res,mod);
}
cout<<res<<endl;
}
return 0;
}
Hi! I have been stuck with this problem for quite some time now but couldn’t seem to figure out where the problem is. I tried a lot of test cases but failed to find where does it fail. Can someone please help me figure out the problem? This is my code:
#include <iostream>
using namespace std;
long long inf = 1000000007;
long long calPow(long long a, long long n){
long long temp;
if(n == 1){
return a;
}
long long t = calPow(a, n/2);
if(n & 1){
temp = t * t;
temp %= inf;
temp = temp * a;
temp %= inf;
return temp;
}
temp = t * t;
temp %= inf;
return temp;
}
int main(void) {
// your code goes here
int t;
cin >> t;
while(t--){
long long n, a;
cin >> n;
cin >> a;
long long p, sum = 0;
for(long long i = 1; i <= n; i++){
long long x = 2*i - 1;
p = calPow(a, x);
sum = (sum + p)%inf;
long long temp;
temp = a * p;
temp %= inf;
a = temp;
}
cout << sum;
}
return 0;
}can anyone help me solve this problem in python 3 , i solved it in c++ but not able to make the power function in python
#include
#include <math.h>
using namespace std;
int main() {
long long int i,j,n,t,x,p1,p2,sum;
cin>>t;
while(t–)
{
cin>>n>>x;
p1=x;
p2=1;
sum=0;
for(i=0;i<n;i++)
{
p1=(p1p2)%(1000000007);
p2=pow(p1,2i+1);
sum=sum+p2%(1000000007);
}
cout<<sum%(1000000007)<<"\n";
}
return 0;
}
im getting WA for this code please help
#include
#include <math.h>
using namespace std;
long long int power(long long int a, long long int b){
if(b == 0)return 1;
if(b%2 == 0){
long long int c = power(a,b/2);
return (cc)%1000000007;
}
return (apower(a,b-1))%1000000007;
}
int main() {
long long int i,j,n,t,x,p1,p2,sum,k;
cin>>t;
while(t–)
{
cin>>n>>x;
p1=x;
p2=1;
sum=0;
for(i=0;i<n;i++)
{A
p1=(p1*p2)%1000000007;
// cout<<p1<<"\n";
//p2=pow(p1,2*i+1);
p2=power(p1,2*i+1);
// cout<<p2<<"\n";
sum=sum+p2%1000000007;
// cout<<p2<<"\n";
}
cout<<sum<<"\n";
}
return 0;
}
can you tell me why i still get WA
you should calculate power using your self power function and take modulo%1000000007 at every step, because for large value of a your power function will give garbage value as output.
refer this link->https://www.geeksforgeeks.org/modular-exponentiation-power-in-modular-arithmetic/
please someone can tell me whats the prob in my code i have done fastexpo as well
https://www.codechef.com/viewsolution/32208721
#include<iostream>
using namespace std;
long long int poww(long long int c,long long int d){
long long int res=1;
while(d--){
res=((res%1000000007)*(c%1000000007))%1000000007;
}
return res%1000000007;
}
int main(){
int t;
cin>>t;
while(t--){
long long int n,a,s=0,p=1;
cin>>n>>a;
for(long long int i=1;i<=n;i++){
p=poww(a,(2*i-1));
s=((s%1000000007)+(p%1000000007))%1000000007;
a=(((p)%1000000007)*((a)%1000000007))%1000000007;
}
cout<<s%1000000007<<endl;
}
return 0;
}
#this code gives me tle. please help.whats wrong in this solution???
#include<bits/stdc++.h>
using namespace std;
#define ll long long
const ll int M = 1e9+7;
ll int n,A;
void solve(){
cin>>n>>A;
ll int sum = 0 ,prod = 1 , count = 1;
for(int i = n - 1 ; i>= 0 ; i--){
prod = pow(A,count);
sum += prod%M;
count+=2;
A = A*prod;
}
cout<<sum<<'\n';
}
int main(){
ios_base::sync_with_stdio(false);
cin.tie(0);
cout.tie(0);
int T;
cin>>T;
while(T–){
solve();
}
return 0;
}