c语言高精度除法运算源代码

<code class="c">#include <stdio.h>
#include <stdlib.h>
#include <string.h>

// 最大数字长度
#define MAX_DIGITS 1000

// 定义高精度整数结构
typedef struct BigInteger {
    int digits[MAX_DIGITS];
    int length;
} BigInteger;

// 初始化高精度整数
void initBigInteger(BigInteger *bi) {
    memset(bi->digits, 0, sizeof(bi->digits));
    bi->length = 0;
}

// 从字符串创建高精度整数
BigInteger *createBigInteger(char *num) {
    BigInteger *bi = malloc(sizeof(BigInteger));
    initBigInteger(bi);

    int len = strlen(num);
    for (int i = len - 1; i >= 0; i--) {
        bi->digits[bi->length++] = num[i] - '0';
    }

    return bi;
}

// 高精度除法运算
BigInteger *divide(BigInteger *dividend, BigInteger *divisor) {
    // 如果除数为 0，则抛出错误
    if (divisor->length == 0) {
        printf("除数不能为 0.\n");
        return NULL;
    }

    // 初始化商和余数
    BigInteger *quotient = malloc(sizeof(BigInteger));
    initBigInteger(quotient);
    BigInteger *remainder = malloc(sizeof(BigInteger));
    initBigInteger(remainder);

    // 将被除数复制到余数中
    memcpy(remainder->digits, dividend->digits, sizeof(dividend->digits));
    remainder->length = dividend->length;

    // 进行除法运算
    int i, j, tmp;
    for (i = 0; i < remainder->length; i++) {
        // 归一化
        tmp = 0;
        for (j = i; j < remainder->length; j++) {
            tmp = tmp * 10 + remainder->digits[j];
            remainder->digits[j] = tmp / divisor->digits[0];
            tmp %= divisor->digits[0];
        }

        // 更新商
        if (remainder->digits[i] != 0) {
            quotient->digits[quotient->length++] = remainder->digits[i];
        }

        // 将商乘以除数并从余数中减去
        for (j = i; j < remainder->length; j++) {
            tmp = 0;
            for (int k = j; k < remainder->length; k++) {
                tmp = tmp * 10 + quotient->digits[quotient->length - 1] * divisor->digits[k - j];
                remainder->digits[k] -= tmp % 10;
                tmp /= 10;
            }
        }

        // 去除余数中的前导 0
        while (remainder->length > 0 && remainder->digits[remainder->length - 1] == 0) {
            remainder->length--;
        }
    }

    // 释放内存
    free(remainder);

    return quotient;
}

// 打印高精度整数
void printBigInteger(BigInteger *bi) {
    int i;
    for (i = bi->length - 1; i >= 0; i--) {
        printf("%d", bi->digits[i]);
    }
}

// 测试用例
int main() {
    char *dividend_str = "12345678901234567890";
    char *divisor_str = "12345";

    BigInteger *dividend = createBigInteger(dividend_str);
    BigInteger *divisor = createBigInteger(divisor_str);

    BigInteger *quotient = divide(dividend, divisor);

    printf("商：");
    printBigInteger(quotient);
    printf("\n");

    return 0;
}</code>