Циклы,Оператор выбора

//---------------------------------------------------------------------------
#include <stdio.h>
#include <math.h>
#include <conio.h>
#include <vcl.h>
//---------------------------------------------------------------------------
int main()
{float s=0,n,x; int k;
k:clrscr();
printf("Vvedite n\nn="); scanf("%f",&n);
for(x=1;x<=n;x*=2)
{s+=1-(1/2)+(1/4)-(1/8)+(pow((-1),n)*1/pow(2,n));}
printf("s=%8.4f",s);
int m;
printf("\nPovtorit' vvod?");
switch (m)
{case 1:k;break;
case 2:exit;}
getch();
 
       return 0;
}
//---------------------------------------------------------------------------

//---------------------------------------------------------------------------
#include <stdio.h>
#include <math.h>
#include <conio.h>
#include <vcl.h>
//---------------------------------------------------------------------------
int main()
{float s=0,n,x; int k;
clrscr();
m1:printf("Vvedite n\nn="); scanf("%f",&n);
for(x=1;x<=n;x*=2)
{s+=1-(1/2)+(1/4)-(1/8)+(pow((-1),n)*1/pow(2,n));}
printf("s=%8.4f",s);
int m;
printf("\nPovtorit' vvod?");
switch (m)
{case 1:goto m1; break;   //Как правильно записать?
case 2:exit;}
getch();
 
       return 0;
}
//---------------------------------------------------------------------------

switch (m)
{case da:goto m1; break;   
case net:exit;

printf("Povtorit' vvod?");
switch(m)
{case 1:-----;}

char select[4];
do
{
    std::cout<<"Povtorit' vvod?"<<std::endl;
    std::cin.getline(select, 4);
}while(strcmp(select, "no"));