高精度模板算法必備

1、-5 -注意：減法、除法要用到compare函數(shù)乘法需要加法的部分，加法需要減法部分#include <iostream>#include <string>using namespace std;int compare(string strl, string str2)(if(str1.size() > str2.size()return 1;else if(str1.size() < str2.size()return -1;elsereturn pare(str2); int main()(char ch;string s1, s2, res;while

2、(cin >> ch) (cin >> s1>> s2;switch(ch) (高精度加法高精度減法高精度乘法高精度除法,返回商高精度除法,返回余數(shù)case '+': res = ADD_INT(s1, s2); break; /case '-': res = MINUS_INT(s1, s2); break; /case '*': res = MULTIPLY_INT(s1, s2); break; /case '/': res = DIV_INT(s1, s2); break; /case

3、'm': res = MOD_INT(s1, s2); break; / default : break;cout << res<< endl;return(0);/高精度加法string ADD_INT(string strl, string str2)string MINUS_INT(string strl, string st；int sign = 1;string str；if(str10 = '-') if(str20 = '-') sign = -1;str = ADD_INT(str1.erase(0, 1)

4、, str2.erase(0, 1);else str = MINUS_INT(str2, str1.erase(0, 1);else if(str20 = '-')str = MINUS_INT(str1, str2.erase(0, 1);else string:size_type l1, l2;int i; -l1 = str1.size(); l2 = str2.size();if(l1 < l2) for(i = 1; i <= (int)(l2 - l1); i+)str1 = "0" + str1;else for(i = 1; i

5、 <= (int)(l1 - l2); i+) str2 = "0" + str2;int int1 = 0, int2 = 0;for(i = str1.size() - 1; i >= 0; i-) int1 = (int(str1i) - 48 + int(str2i) - 48 + in t2) %10;int2 = (int(str1i) - 48 + int(str2i) - 48 +int2) / 10;str = char(int1 + 48) + str;if(int2 != 0) str = char(int2 + 48) + str;/運算

6、后處理符號位if(sign = -1) && (str0 !='0')str = "-" + str;return str;/高精度減法string MINUS_INT(string strl, string ststring MULTIPLY_INT(string strl, string st；int i,sign = 1;string str；if(str20='-')str = ADD_INT(str1, str2.erase(0, 1);else int res = compare(str1, str2);if(re

7、s = 0) return "0”;if(res < 0) sign = -1;string temp = str1;str1 = str2;str2 = temp;string:size_type tempint;tempint = str1.size() - str2.size();for(int i = str2.size() - 1; i >= 0; i-) if(str1i + tempint < str2i) str1i + tempint - 1 = char(int(str1i + tempint - 1) - 1);str = char(str1i

8、 + tempint - str2i + 58) + str;elsestr = char(str1i + tempint - str2i + 48) + str;for(i = tempint - 1; i >= 0; i-) str = str1i + str;/去除結果中多余的前導0str.erase(0, str.find_first_not_of('0');if(str.empty() str = "0"if(sign = -1) && (str0 !='0')str = "-" + str

9、;return str;/高精度乘法string MULTIPLY_INT(string strl, string stint sign = 1;string str;if(str10 = '-') sign *= -1;str1 = str1.erase(0, 1);if(str20 = '-') sign *= -1;str2 = str2.erase(0, 1);int i, j;string:size_type l1, l2;l1 = str1.size(); l2 = str2.size();for(i = l2 - 1; i >= 0; i -

10、) /實現(xiàn)手工乘法string tempstr;int int1 = 0, int2 = 0, int3 = int(str2i) - 48;if(int3 != 0) for(j = 1; j <= (int)(l2 - 1 - i); j+) tempstr = "0" + tempstr;for(j = l1 - 1; j >= 0; j-) int1 = (int3 * (int(str1j) - 48) + int2) % 10;int2 = (int3 * (int(str1j) - 48) + int2) / 10;tempstr = char(i

11、nt1 + 48) + tempstr;if(int2 != 0) tempstr = char(int2 + 48) + tempstr;str = ADD_INT(str, tempstr);/去除結果中的前導0str.erase(0, str.find_first_not_of('0');if(str.empty() str = "0"if(sign = -1) && (str0 !='0')str = "-" + str;return str;/高精度除法string DIVIDE_INT(stri

12、ng strl, string str2, int flag)/flag = 1 時,返回W ; flag = 0時,返回余數(shù)string quotient, residue;int sign1 = 1, sign2 = 1, i;if(str2 = "0") /判斷除數(shù)是否為0quotient = "ERROR!"residue = "ERROR!"if(flag = 1) return quotient;else return residue;if(str1 = "0") /判斷被除數(shù)是否為0quotient

13、= "0"residue = "0"if(str10 = '-') strl = str1.erase(0, 1);signl *= -1;sign2 = -1;if(str20 = '-') str2 = str2.erase(0, 1);sign1 *= -1;int res = compare(str1, str2);if(res < 0) quotient = "0"residue = str1;else if(res = 0) quotient = "1"residu

14、e = "0"else string:size_type 11, 12;11 = str1.size(); 12 = str2.size();string tempstr;tempstr. append(str1,0, 12 - 1);/模擬手工除法for(i = 12 - 1; i < 11; i+) tempstr = tempstr + str1i;for(char ch = '9' ch >= '0' ch -) string str;str = str + ch;if(compare(MULTIPLY_INT(str2,

15、 str), tempstr) <= 0)(quotient = quotient + ch;tempstr = MINUS_INT(tempstr, MULTIPLY_INT(str2, str);break;residue = tempstr;/去除結果中的前導0quotient.erase(0, quotient.find_first_not_of('0');if(quotient.empty() quotient = "0"if(sign1 = -1) && (quotient0 !='0')quotient = "-" + quotient;if(sign2 = -1) && (residue0 !='0') res