Data structure (Yan Weimin) computing 1-1/x + 1/x * x... (Chapter 1)

/* Algo1-1.c computing 1-1/x + 1/x * x...
Computing

*/
# Include <stdio. h>
# Include <sys/timeb. h>
# Include <iostream>
 
Int main ()
{
Struct timeb T1, T2;
Long T;
Double X, sum = 1, sum1;
Int I, j, N;
Printf ("Enter x N :");
Scanf ("% lf % d", & X, & N );
Ftime (& T1);/* obtain the current time */
For (I = 1; I <= N; I ++)
{
Sum1 = 1;
For (j = 1; j <= I; j ++)
Sum1 =-sum1/X;
Sum + = sum1;
}
Ftime (& T2);/* obtain the current time */
T = (t2.time-t1.time) * 1000 + (t2.millitm-t1.millitm);/* calculate the time difference */
Printf ("sum = % lf % LD millisecond/N", sum, t );
System ("pause ");
Return 1;
}

 

Algorithm 2

/* Algo1-2.cpp computing 1-1/x + 1/x * x... Faster Algorithm */
# Include <stdio. h>
# Include <sys/timeb. h>
Void main ()
{
Struct timeb T1, T2;
Long T = 0;
Double X, sum1 = 1, sum = 1;
Int I, N;
Printf ("Enter x N :");
Scanf ("% lf % d", & X, & N );
Ftime (& T1);/* obtain the current time */
For (I = 1; I <= N; I ++)
{
Sum1 =-sum1/X;
Sum + = sum1;
}
Ftime (& T2);/* obtain the current time */
T = (t2.time-t1.time) * 1000 + (t2.millitm-t1.millitm);/* calculate the time difference */
Printf ("sum = % lf % LD millisecond/N", sum, t );
}