How many options have 1,000 representatives in the 150 million population in the country?

Fast combination c (n, k) = n * (n-1) * (N-2) * ... * (N-K 1) / 1 * 2 * 3 * ... * K conquest:

Function ZDGYS (BYVAL X As Long, Byval Y As Long AS Long 'GET GREATEST COMMON DIVISOR Maximum DIM TEMP AS Long IF X> Y THEN TEMP = x: x = Y: Y = Temp' Let x 0 and K = 0 Then CNK = 1: Goto R' Special Situation IF K> N - K THEN K = N - K 'Reduces the amount of computation DIM NN () As long, nk () As longredim nn (1 to k) redim NK (1 to k) for i = 1 to kNN (i) = n 1 - i 'N * (n-1) * (n-2) * .... * (n 1-k) NK (i) = i' 1 * 2 * 3 * ... * KNext

For i = k to 1 step -1 for j = 1 to k TEMP = zdgys (nk (j), NN (i)) 'maximum number of conventions IF TEMP> 1 THEN' eliminating molecular denominator NN (i) = nn (i ) / Temp nk (j) = nk (j) / temp end if Nextnext

Redim x (1) redim xys (1) x (1) = 1 'initialization array xys (1) = 1t = 1

Do While NOT T> K

Temp = len (cstr (NN (t))) Redim Y (1 to Temp) for i = 1 to Tempy (i) = VAL (MID (NN (T), Temp 1 - I, 1)) NEXTREDIM XYS 1 to Ubound (x) Ubound (Y)) for i = 1 to Ubound (x) for j = 1 to Ubound (Y) XYS (i J - 1) = xys (i j - 1) x ( I) * Y (j) 'analog multiplication method NextNextFor i = 1 to Ubound (x) ubound (y) - 1' carry TEMP = Xys (i) / 10XYS (i) = xys (i) MOD 10XYS (i 1) = xys (i 1) TempNextt = T 1X = xysif x (Ubound (x)) = 0 THEN Redim preserve x (1 to Ubound (x) - 1) 'First bit is zero LOOP

Redim Result (1 to Ubound (x)) 'Billy assignment for i = 1 to Ubound (x) Result (i) = x (ubound (x) 1 - i) Next

CNK = JOIN ("" ") 'Last Result R: Debug.print" C ("& N &", "& K &") = "& CNK & VBCRLF &" Time "; Timer - Stimer &" Second, The results are about "& Val (Left (CNK, 3)) / 100 &" * 10 ^ "& len (cn) - 1Erase X () 'Release ERASE Y () ERASE XYS () ERASE RESULT () ERASE NN () ERASE NK ()

End Sub

Private Sub Command1_Click () Calc 1500000000, 1000und Sub

C (1500000000, 1000) =

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