大数乘法（大数乘小数）c语言版

#include <stdio.h>#include <string.h>#define N 100   //数组的大小，可以设置//返回数组的长度int  mult(const char *a, int m, char *result){int i;     //循环变量int flag;  //进位的标志int num;int c = 0;     //进位数int Len = strlen(a);int k = 0;char s[N];  //临时的数组for(i = Len - 1; i >=0 ; i--){num = (a[i] - '0') * m + c;if(num > 9){s[k++] = num % 10;c = num / 10;flag = 1;}else{s[k++] = num;flag = 0;c = 0;}}if(flag){Len++;s[k] = c;}for(i = 0; i < Len; i++)result[Len - i -1] = s[i] + '0';result[Len] = '\n';return Len;}