NC359. 大数相减
描述
数据范围：两个数字的长度都满足 
，数字中仅包含 
，第一位不可能是0
示例1
输入:
"100000000","1"
输出:
"99999999"
示例2
输入:
"100000000","1000000000"
输出:
"-900000000"
NC359. 大数相减
描述
示例1
输入:
"100000000","1"
输出:
"99999999"
示例2
输入:
"100000000","1000000000"
输出:
"-900000000"
C++ 解法, 执行用时: 5ms, 内存消耗: 1456KB, 提交时间: 2022-07-28
static const auto io_sync_off = [](){
std::ios::sync_with_stdio(false);
std::cout.tie(nullptr);
std::cin.tie(nullptr);
return nullptr;
}();
class Solution {
public:
string substring(string num1, string num2) {
int z=0;
if(num1.size()<num2.size()||num1.size()==num2.size()&&num1<num2)
{
swap(num1,num2);
z=1;
}
int l1=num1.size()-1;
int l2=num2.size()-1;
string r;
int b=0;
while(l1>=0||l2>=0)
{
int n1=l1>=0?num1[l1--]-'0':0;
int n2=l2>=0?num2[l2--]-'0':0;
int temp=n1-n2-b;
b=0;
if(temp<0)
{
b=1;
temp+=10;
}
r+=temp+'0';
}
reverse(r.begin(),r.end());
r.erase(0,r.find_first_not_of('0'));
if(r.size()==0)
return "0";
if(z==0)
return r;
else r='-'+r;
return r;
}
};
C++ 解法, 执行用时: 6ms, 内存消耗: 1444KB, 提交时间: 2022-08-06
static const auto io_sync_off = [](){
std::ios::sync_with_stdio(false);
std::cout.tie(nullptr);
std::cin.tie(nullptr);
return nullptr;
}();
class Solution {
public:
/**
* 代码中的类名、方法名、参数名已经指定，请勿修改，直接返回方法规定的值即可
*
*
* @param num1 string字符串
* @param num2 string字符串
* @return string字符串
*/
string substring(string num1, string num2) {
// write code here
int z=0;
if(num1.size()<num2.size()||num1.size()==num2.size()&&num1<num2)
{
swap(num1,num2);
z=1;
}
int l1=num1.size()-1;
int l2=num2.size()-1;
string r;
int b=0;
while(l1>=0||l2>=0)
{
int n1=l1>=0?num1[l1--]-'0':0;
int n2=l2>=0?num2[l2--]-'0':0;
int temp=n1-n2-b;
b=0;
if(temp<0)
{
b=1;
temp+=10;
}
r+=temp+'0';
}
reverse(r.begin(),r.end());
r.erase(0,r.find_first_not_of('0'));
if(r.size()==0)
return "0";
if(z==0)
return r;
else
r='-'+r;
return r;
}
};
Go 解法, 执行用时: 7ms, 内存消耗: 2860KB, 提交时间: 2022-07-04
package main
import "strings"
func substring(num1 string, num2 string) string {
f := cmp(num1, num2)
if !f {
num1, num2 = num2, num1
}
H, h := len(num1)-1, len(num2)-1
w := 0
z := strings.Builder{}
for H >= 0 || h >= 0 {
u, v := 0, 0
if H >= 0 {
u = int(num1[H] - '0')
}
if h >= 0 {
v = int(num2[h] - '0')
}
if u-w >= v {
z.WriteByte(byte(u - w - v + '0'))
w = 0
} else {
z.WriteByte(byte(u - w - v + 10 + '0'))
w = 1
}
H--
h--
}
str := z.String()
sh := len(str) - 1
for sh > 0 {
if str[sh] != '0' {
break
}
sh--
}
str = str[:sh+1]
str = reverse(str)
if !f {
str = "-" + str
}
return str
}
func cmp(a, b string) bool {
if len(a) == len(b) {
return a >= b
} else if len(a) > len(b) {
return true
}
return false
}
func reverse(str string) string {
s := []byte(str)
for i := 0; i <= (len(s)-1)/2; i++ {
s[i], s[len(s)-1-i] = s[len(s)-1-i], s[i]
}
return string(s)
}
C++ 解法, 执行用时: 8ms, 内存消耗: 1416KB, 提交时间: 2022-04-17
class Solution {
public:
/**
* 代码中的类名、方法名、参数名已经指定，请勿修改，直接返回方法规定的值即可
*
*
* @param num1 string字符串
* @param num2 string字符串
* @return string字符串
*/
bool compare(string num1, string num2){
if(num1.length()<num2.length())
return false;
else if (num1.length()>num2.length()) {
return true;
}
else {
return num1 > num2;
}
}
string substring(string num1, string num2) {
// write code here
char sign = '+';
if(!compare(num1,num2)){
sign = '-';
swap(num1,num2);
}
int p1 = num1.length()-1;
int q1 = num2.length()-1;
string res;
int borrow = 0;
while (p1 >=0 || q1>=0) {
int n1=p1>=0?(num1[p1--]-'0'):0;
int n2=q1>=0?(num2[q1--]-'0'):0;
int num = n1 - n2 - borrow;
borrow = 0;
if(num < 0){
borrow = 1;
num += 10;
}
res+=num+'0';
}
reverse(res.begin(),res.end());
res.erase(0,res.find_first_not_of('0'));
if(res.length()==0)
return "0";
if(sign=='+')
return res;
res = sign + res;
return res;
}
};
Go 解法, 执行用时: 8ms, 内存消耗: 2516KB, 提交时间: 2022-03-29
package main
import (
"strings"
// "fmt"
)
/**
* 代码中的类名、方法名、参数名已经指定，请勿修改，直接返回方法规定的值即可
*
*
* @param num1 string字符串
* @param num2 string字符串
* @return string字符串
*/
func substring( num1 string , num2 string ) string {
flag := cmp(num1, num2)
if !flag {
num1, num2 = num2, num1
}
index1, index2 := len(num1) - 1, len(num2) - 1
borrow := 0
res := strings.Builder{}
for index1 >= 0 || index2 >= 0 {
upper, lower := 0, 0
if index1 >= 0 { upper = int(num1[index1] - '0')}
if index2 >= 0 { lower = int(num2[index2] - '0')}
if upper - borrow >= lower {
res.WriteByte(byte(upper-borrow-lower + '0'))
borrow = 0
} else {
res.WriteByte(byte(upper-borrow-lower+10 + '0'))
borrow = 1
}
index1--
index2--
}
rr := res.String()
pos := len(rr)-1
for pos > 0 {
if rr[pos] != '0' { break }
pos--
}
rr = rr[:pos+1]
rr = reverse(rr)
// fmt.Println(rr)
if !flag {
rr = "-" + rr
}
return rr
}
func cmp(a, b string) bool {
if len(a) == len(b) {
return a >= b
} else if len(a) > len(b) {
return true
}
return false
}
func reverse(rr string) string {
r := []byte(rr)
for i := 0; i <= (len(r) - 1)/2; i++ {
r[i], r[len(r)-1-i] = r[len(r)-1-i], r[i]
}
return string(r)
}