#include <stdio.h>
#include <math.h>
int main(void)
{
        int n_terms;
        double x,y,Y,r_error=0;
        printf("Enter x: ");
        scanf("%lf",&x);
        printf("\n");
        y=log(1+x);
        printf("True value of ln(1+0.25000) = %.5f\n\n",y);
        do{
        printf("Enter a number 1-5 (0 to exit):\n");
        scanf("%d",&n_terms);
        printf("%d term(s) approximation\n",n_terms);
        switch(n_terms){
                case 5:
                        Y+=pow(x,5)/5;
                case 4:
                        Y-=pow(x,4)/4;
                case 3:
                        Y+=pow(x,3)/3;
                case 2:
                        Y-=pow(x,2)/2;
                case 1:
                        Y=x;
                        break;
                default:
                        if(n_terms!=0){
                                printf("unrecognized operator");
                                continue;
                                        }
                printf("Approximate ln(1+0.25000) = %.5d\n",Y);
                r_error=100*(Y-y)/y;
                printf("Relative Error = %.5d%\n\n",r_error);
        }
                        }while(n_terms!=0);
}