Coursera's Algorithmic toolbox assignment solutions( Last Digit of the Sum of Fibonacci Numbers Again, Last Digit of the Sum of Squares of Fibonacci Numbers ) :

Problem 7:  Last Digit of the Sum of Fibonacci Numbers Again

Solution: (in c++)

( please guys before moving to the solution try it yourself at least 3-4 times , if you really wanna become a good coder)

#include <bits/stdc++.h>

using namespace std;

long long unsigned fib(long long unsigned p) //function to calculate nth fib. number

{

long long unsigned f[p],i;

f[0]=0;

f[1]=1;

for(i=2;i<=p;i++)

{

f[i]=(f[i-1]+f[i-2])%10;

}

return f[p];

}

int main()

{

long long unsigned n,i,sum=0,m;

cin>>n>>m;

for(i=n;i<=m;i++)

{

sum+=fib(i);

}

cout<<sum%10;

}

This code is simple. There's no need for any explanation.

 

 

 

 

Problem 8: Last Digit of the Sum of Squares of Fibonacci Numbers

Solution: (in c++)

( please guys before moving to the solution try it yourself at least 3-4 times , if you really wanna become a good coder)

Still working on this solution...

But for small test cases this code will work fine.

#include <bits/stdc++.h>

using namespace std;

int main()

{

long long unsigned n,i,p,q;

cin>>n;

long long unsigned f[n];

f[0]=0;

f[1]=1;

for(i=2;i<=n+1;i++)

{

f[i]=(f[i-1]+f[i-2])%10;

p=f[n]%10;

q=f[n+1]%10;

}

cout<<(p*q)%10;

}

 

 

 

Guys , if you have any queries related to a question or need more explanation, comment down below!