PROGRAM TO FIND SUMMATION OF THE SERIES

//PROGRAM TO FIND SUMMATION OF THE SERIES
/*MADE BY KRISHNA AGARWAL*/
#include<iostream>
#include<math.h>
using namespace std;
int main()
{
    int i,k,n;
    float s=0;
    cout<<"\n PRESS THE KEY FOR DESIRED SUMMATION\n";
    cout<<"\n PRESS 1 FOR 1+4+9+........n*n\n";
    cout<<"\n PRESS 2 FOR 1+8+27+.......n*n*n\n";
    cout<<"\n PRESS 3 FOR sqrt(1)+sqrt(2)+....sqrt(n)\n";
    cin>>n;
    switch(n)
    {
        case 1:
            cout<<"\n ENTER THE NUMBER OF TERMS IN THE SERIES\n";
            cin>>k;
            for(i=1;i<=k;i++)
                s=s+i*i;
            cout<<"\n THE VALUE OF THE SUMMATION IS\t"<<s;
            break;
        case 2:
            cout<<"\n ENTER THE NUMBER OF TERMS IN THE SERIES\n";
            cin>>k;
            for(i=1;i<=k;i++)
                s=s+i*i*i;
            cout<<"\n THE VALUE OF THE SUMMATION IS\t"<<s;
            break;
        case 3:
            cout<<"\n ENTER THE NUMBER OF TERMS IN THE SERIES\n";
            cin>>k;
            for(i=1;i<=k;i++)
                s=s+sqrt(i);
                cout.precision(3);
            cout<<"\n THE VALUE OF THE SUMMATION IS\t"<<s;
            break;
    }
    return 0;
}