#include
<
stdio.h
>
int binary_search( int x, int data[], int b, int e)
{
int i;
while (b <= e)
{
i = (b + e) / 2 ;
if (data[i] == x) return i;
if (data[i] < x)
b = i + 1 ;
else
e = i - 1 ;
}
return - 1 ;
}
int binary_search_recursion( int x, int data[], int b, int e)
{
int i;
i = (b + e) / 2 ;
if (b > e) return - 1 ;
if (data[i] != x)
{
if (x < data[i])
return binary_search_recursion(x, data, 0 , i - 1 );
else
return binary_search_recursion(x, data, i + 1 , e);
}
else
return i;
}
int main()
{
int data[] = { 1 , 4 , 5 , 7 , 9 };
printf( " %d \n " , binary_search_recursion( 9 , data, 0 , 4 ));
printf( " %d \n " , binary_search( 9 , data, 0 , 4 ));
printf( " %d \n " , binary_search_recursion( 90 , data, 0 , 4 ));
printf( " %d \n " , binary_search( 89 , data, 0 , 4 ));
return 0 ;
}
int binary_search( int x, int data[], int b, int e)
{
int i;
while (b <= e)
{
i = (b + e) / 2 ;
if (data[i] == x) return i;
if (data[i] < x)
b = i + 1 ;
else
e = i - 1 ;
}
return - 1 ;
}
int binary_search_recursion( int x, int data[], int b, int e)
{
int i;
i = (b + e) / 2 ;
if (b > e) return - 1 ;
if (data[i] != x)
{
if (x < data[i])
return binary_search_recursion(x, data, 0 , i - 1 );
else
return binary_search_recursion(x, data, i + 1 , e);
}
else
return i;
}
int main()
{
int data[] = { 1 , 4 , 5 , 7 , 9 };
printf( " %d \n " , binary_search_recursion( 9 , data, 0 , 4 ));
printf( " %d \n " , binary_search( 9 , data, 0 , 4 ));
printf( " %d \n " , binary_search_recursion( 90 , data, 0 , 4 ));
printf( " %d \n " , binary_search( 89 , data, 0 , 4 ));
return 0 ;
}