本文实例为大家分享了C++实现浮点数精确加法的具体代码，供大家参考，具体内容如下

实现两个正浮点数的精确加法

参与运算的浮点数及计算结果所需存储空间都不会超过main函数中的定义

main函数框架要求如下：

int main(){ char num1[128],num2[128],res[128]; cout<<"Enter the first number:"; cin>>num1; cout<<"Enter the second number:"; cin>>num2; add(num1,num2,res); cout<<num1<<'+'<<num2<<'='<<res<<endl; return 0;}

C++实现：

#include <iostream>using namespace std;void add(char num1[], char num2[], char res[]);int get_len(char num[]);int get_integer(char num[]);int get_dot(char num[]);int get_decimal_len(char num[]);int get_integer_len(int x);int char_to_int(char num[], int begin, int len);void int_to_char(char res[], int x);void get_decimal(char num1[], char num2[]);char decimal[128] = {0};int main() { char num1[128] = {0}, num2[128] = {0}, res[128] = {0}; cout << "Enter the first number:"; cin >> num1; cout << "Enter the second number:"; cin >> num2; add(num1, num2, res); cout << num1 << '+' << num2 << '=' << res << endl; return 0;}//获取小数点在哪一位int get_dot(char num[]) { int i; for (i = 0; num[i] != '\0'; ++i) { if (num[i] == '.') { return i; } } return i;}//把字符串转化为整数int char_to_int(char num[], int begins, int len) { int integer = 0, l = get_decimal_len(num); if (l < len) { for (int j = l; j <= len; ++j) { num[begins + j + 1] = '0'; } } for (int i = 0; i < len; ++i) { integer = integer * 10 + num[begins + i + 1] - '0'; } return integer;}//整数转化为字符串void int_to_char(char res[], int x) { int i, l = get_integer_len(x); for (i = l - 1; i >= 0; --i) { res[i] = x % 10 + '0'; x /= 10; } res[l + 1] = '\0';}//得到整数部分int get_integer(char num[]) { int integer = 0, x = get_dot(num); for (int i = 0; i <= x - 1; ++i) { integer = integer * 10 + num[i] - '0'; } return integer;}//得到小数部分长度int get_decimal_len(char num[]) { int x = get_dot(num), len = 0; for (int i = x + 1; num[i] != '\0'; ++i)len++; return len;}//得到整数的长度int get_integer_len(int x) { int integer_len = 0; if (x == 0)return 1; while (x > 0) { x /= 10; integer_len++; } return integer_len;}//得到字符串长度int get_len(char num[]) { int sum = 0; for (int i = 0; num[i] != '\0'; ++i) sum++; return sum;}//得到小数变成整数后的和void get_decimal(char num1[], char num2[]) { int decimal_len = get_decimal_len(num1) > get_decimal_len(num2) ? get_decimal_len(num1) : get_decimal_len(num2); int decimal_sum = char_to_int(num1, get_dot(num1), decimal_len) + char_to_int(num2, get_dot(num2), decimal_len); int_to_char(decimal, decimal_sum); if (decimal_len < get_integer_len(decimal_sum)) { for (int i = 0; decimal[i] != '\0'; ++i) { decimal[i] = decimal[i + 1]; } }}void add(char num1[], char num2[], char res[]) { bool flag = false, zero_flag = false; int i; int l1 = get_len(num1), l2 = get_len(num2); get_decimal(num1, num2); int decimal_len = get_decimal_len(num1) > get_decimal_len(num2) ? get_decimal_len(num1) : get_decimal_len(num2); int decimal_sum = char_to_int(num1, get_dot(num1), decimal_len) + char_to_int(num2, get_dot(num2), decimal_len); if (decimal_len < get_integer_len(decimal_sum)) { flag = true; } int sum_int = get_integer(num1) + get_integer(num2) + flag; int_to_char(res, sum_int); *(res + get_integer_len(sum_int)) = '.'; for (i = 1; decimal[i - 1] != '\0'; ++i) { *(res + get_integer_len(sum_int) + i) = decimal[i - 1]; } for (i = get_dot(res) + 1; res[i] != '\0'; ++i) { if (res[i] != '0') { zero_flag = true; } } if (!zero_flag) { res[get_dot(res)] = '\0'; } else { for (i = get_len(res) - 1; i > get_dot(res); --i) { if (res[i] == '0') { res[i] = '\0'; break; } break; } } num1[l1] = '\0', num2[l2] = '\0';}

总结：

• 用整型数组来储存各个位数的数字
• 学会进位制，悟透进位原理
• 熟练掌握字符串数组与整型数组的相互转换
• 学会用指针来辅助输出
  

以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持。