42 lines
1.1 KiB
C
42 lines
1.1 KiB
C
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#include <stdio.h>
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#include <math.h>
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#include <stdlib.h>
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#include <string.h>
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// 递归计算大整数乘积
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double bigdataride(long x, long y, int n) {
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x = llabs(x); y = llabs(y);
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if (n == 1) {
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return (double)x * y; // 基本情况
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} else {
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if (n % 2 == 1) n--; // 处理奇数位
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long halfPow = (long)pow(10, n / 2);
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long a = x / halfPow;
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long b = x % halfPow;
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long c = y / halfPow;
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long d = y % halfPow;
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// 递归计算
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double ac = bigdataride(a, c, n / 2);
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double bd = bigdataride(b, d, n / 2);
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long aJb = a + b;
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long cJd = c + d;
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double abcd = bigdataride(aJb, cJd, n / 2);
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// 返回最终结果
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return ac * pow(10, n) + (abcd - ac - bd) * pow(10, n / 2) + bd;
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}
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}
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int main() {
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long x = 8782346786879887887L;
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long y = 4524387689998798768L;
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// 计算数字长度
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char sx[20];
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snprintf(sx, sizeof(sx), "%ld", x);
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int n = strlen(sx);
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// 计算并输出结果
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double s = bigdataride(x, y, n);
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printf("大数相乘的计算结果为：%lf\n", s);
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return 0;
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}
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