Calculate the factorial of n. the maximum number is 9999!

C language core (Source Network ):

# Define N 8 // calculate the factorial of n. the maximum number is 9999 <br/> long a [8916] = {}, N, I, C, Len; <br/> int main () <br/> {<br/> N = N; <br/> for (LEN = 1; n> 1; n --) <br/> {<br/> for (C = 0, I = 0; I <Len; I ++) <br/>{< br/> long P = A [I] * n + C; <br/> A [I] = P % 10000; <br/> C = P/10000; <br/>}< br/> A [I] = C; <br/> If (C> 0) <br/> Len ++; <br/>}< br/> printf ("% d", a [len-1]); <br/> for (Len --; len> = 0; Len --) <br/> printf ("% 04d", a [Len]); <br/> system ("pause "); <br/> return 0; <br/>}< br/>I used the Assembly to rewrite it:; $ $ <Br/>; -=-factorial by G-spider @ 2010 <br/>;-=-ml/C/coff factorial. ASM <br/>;-=-link/subsystem: Console factorial. OBJ <br/>;-=-invoke MessageBox, 9999, <br/>;-=-_ factorial function can be up! <Br/>;-=-exit by Q or q <br/>; $ $ <br/>. 386 <br/>. model flat, stdcall </P> <p> include user32.inc <br/> include kernel32.inc <br/> include msvcrt. INC </P> <p> includelib user32.lib <br/> includelib kernel32.lib <br/> includelib msvcrt. lib <br/>. data <br/> fmt0 dB '% d! = % D', 0 <br/> fmt1 dB '% 04d', 0 <br/> fmt2 dB 0dh, 0ah, 0 <br/> Inform dB 'Please input num (0 ~ 999): ', 0dh, 0ah, 0 <br/> outform dB 'Please re-input num 0 ~ 999 or Q-Exit: ', 0dh, 0ah, 0 <br/> szpause dB 'pause', 0 <br/> dwstrlen dd 8916 </P> <p>. data? <Br/> lpoutputbuf dd? <Br/> Len dd? <Br/>. code <br/>; * ************************** </P> <p> _ factorial proc LPA: DWORD, N: DWORD <br/> Local @ C, @ Len </P> <p> mov @ Len, 1 <br/> mov ESI, LPA <br/> cmp n, 0 <br/> je exit <br/> loop1: <br/> mov @ C, 0 <br/> xor ebx, EBX <br/>: <br/>; P = A [I] * n + C; <br/> mov eax, [ESI + EBX * 4] <br/> imul eax, n <br/> Add eax, @ C </P> <p> CDQ <br/> mov ECx, 10000; base: 10000 <br/> idiv ECx <br/> mov [ESI + EBX * 4], EDX <br/> mov @ C, eax </P> <p> Inc EBX <br/> cmp ebx, @ Len <br/> JB @ B </P> <p> mov [ESI + EBX * 4], eax <br/> CMP eax, 0 <br/> jbe a00 <br/> Inc @ Len <br/> a00: <br/> dec n <br/> cmp n, 1 <br/> ja loop1 <br/> Exit: <br/> mov eax, @ Len <br/> RET <br/> _ factorial endp <br/>; **************************** <br/> _ INPUT proc <br/> Local @ num <br/> mov @ num, 0 <br/>@:< br/> invoke crt_getchar <br/> mov EBX, eax </P> <p>. if EBX = 'q' | EBX = 'q' <br/> invoke exitprocess, 0 </P> <p>. elseif EBX> = '0' & EBX <= '9' <br/> mov ECx, @ num <br/> imul ECx, 10 <br/> sub EBX, '0' <br/> Add ECx, EBX <br/> mov @ num, ECx <br/>. elseif EBX = 0ah <br/> mov eax, @ num <br/>. if eax <0 | eax> 999;> 9999 <br/> invoke crt_printf, offset outform <br/> mov @ num, 0 <br/> JMP @ B <br/>. endif <br/> RET <br/>. endif <br/> JMP @ B <br/> _ INPUT endp </P> <p>; * *************************** <br/> _ output proc lpbuf: DWORD, @ num: DWORD <br/> invoke _ factorial, lpbuf, @ num <br/> dec eax <br/> push ESI <br/> mov ESI, lpbuf </P> <p> invoke crt_printf, offset fmt0, @ num, dword ptr [ESI + eax * 4] <br/> pop ESI <br/> pop eax <br/> test eax, eax <br/> JZ exit <br/> dec eax <br/>: <br/> push eax <br/> push ESI <br/> invoke crt_printf, offset fmt1, dword ptr [ESI + eax * 4] <br/> pop ESI <br/> pop eax <br/> dec eax <br/> JNS @ B <br/> Exit: <br/> invoke crt_printf, offset fmt2 <br/> XOR eax, eax <br/> RET <br/> _ output endp <br/>; * **************************** </P> <p> start: <br/> invoke crt_printf, offset inform <br/> mov eax, dwstrlen <br/> SHL eax, 2 <br/> mov dwstrlen, eax <br/> invoke crt_malloc, eax <br/> mov lpoutputbuf, eax <br/>: <br/> invoke rtlzeromemory, lpoutputbuf, dwstrlen <br/> mov ESI, lpoutputbuf <br/> mov dword ptr [esi], 1 </P> <p> invoke _ INPUT <br/> invoke _ output, lpoutputbuf, eax <br/> JMP @ B </P> <p> end start <br/>