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大整数的＋－× /， 一般是将大整数看做一个字符串，每一位上的数字对应一个字符，然后对字符串进行处理。下面是进行大整数加法运算的例子，其他采用相同的方法可以实现。
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#include <stdio.h>Linux伊甸园论坛(A p?a b{(D%wY
#include <stdlib.h>
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S0W3ym:R2M3d mchar *pa; // 字符串a首地址
1K;PWlPlchar *pb; // 字符串b首地址Linux伊甸园论坛 hP ^a(Axs8^#a
char *p_sum; // 结果字符串Plm/b)~5T
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int len_a = 0; // 字符串a的长度
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void add()
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"C9ay%k(l char *start_a = pa+len_a-1; // 从a的个位开始
/B3O)pch)yO%KioLinux伊甸园论坛 char *start_b = pb+len_b-1; // 从b的个位开始N'j'e7ETm
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char *start_c; // 结果的个位
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len = len_a>len_b?len_a:len_b;Z'WO%`{$m CQ1m~!Y N
p_sum = (char*)malloc((len + 2) * sizeof(char));
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}
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start_a--;
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*start_c = *start_a + carry;
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*start_c = *start_a + carry - 10;Linux伊甸园论坛 WO2W dt-h'C7T
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}
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{
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carry = 0;
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else
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}
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printf("%s + %s = %s\n", pa, pb, start_c);
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char arr_in[SIZE];
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printf("Please input b: ");
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-E]H8i'CLinux伊甸园论坛[ 本帖最后由 xgf 于 2007-10-27 19:00 编辑 ]
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