C 解法, 执行用时: 2ms, 内存消耗: 396KB, 提交时间: 2021-02-28
/**
* 验证IP地址
* @param IP string字符串 一个IP地址字符串
* @return string字符串
*/
int check_ip_as_ipv4(char *ip,int len)
{
int i = 0,val =0,nodeLen =0,nodeNum =0;
if(len > 15 || len < 7)
{
return -1;
}
while(i < len)
{
if(ip[i] == '.')
{
if(i == 0 || ip[i-1]=='.')
return -1;
if(val > 255 || val < 0)
{
return -2;
}
if(val == 0 && nodeLen > 1)
{
return -3;
}
val = 0;
nodeLen = 0;
nodeNum ++;
if(nodeNum > 4)
return -4;
i++;
}
else if(ip[i] < '0' || ip[i] > '9')
return -5;
if(val == 0 && nodeLen >= 1)
{
return -6;
}
val = val*10 +(ip[i]-'0');
nodeLen ++;
i++;
}
return 0;
}
int check_ip_as_ipv6(char *ip,int len)
{
int i = 0,val =0,nodeLen =0,nodeNum =0,tmpVal = 0;
if(len > 39 || len < 15)
{
return -1;
}
while(i < len)
{
if(ip[i] == ':')
{
if(i == 0 || ip[i-1]==':')
return -1;
if(nodeLen > 4)
{
return -2;
}
if(val ==0 && nodeLen ==4)
return -3;
val = 0;
nodeLen = 0;
nodeNum ++;
if(nodeNum > 8)
return -4;
i++;
}
else if((ip[i] >= '0' && ip[i] <= '9'))
{
tmpVal = ip[i]-'0';
}
else if(ip[i] >= 'a' && ip[i] <= 'f')
{
tmpVal = ip[i]-'a'+10;
}
else if(ip[i] >= 'A' && ip[i] <= 'F')
{
tmpVal = ip[i]-'A'+10;
}
else
{
return -6;
}
val = val*16 + tmpVal;
nodeLen ++;
i++;
}
return 0;
}
char* solve(char* IP ) {
// write code here
int len = 0,i=0,ret =0;
if(NULL == IP)
{
return NULL;
}
len = strlen(IP);
while(i<len){
if(IP[i]=='.'){
ret = check_ip_as_ipv4(IP,len);
if(0 == ret){
return "IPv4";}
break;
}
else if(IP[i]==':'){
ret = check_ip_as_ipv6(IP,len);
if(0 == ret)
return "IPv6";
break;
}
i++;
}
return "Neither";
}
C++ 解法, 执行用时: 2ms, 内存消耗: 408KB, 提交时间: 2021-10-05
class Solution {
public:
/**
* 验证IP地址
* @param IP string字符串 一个IP地址字符串
* @return string字符串
*/
vector<string> split(string s, string dev)
{
vector<string> res;
int it;
while((it = s.find(dev)) && it != s.npos)
{
res.push_back(s.substr(0, it));
s = s.substr(it + 1);
}
res.push_back(s);
return res;
}
bool isIPv4(string IP)
{
if(IP.size() < 7 || IP[0] == '.' || IP[IP.length() - 1] == '.') return false;
vector<string> str = split(IP, ".");
if(str.size() != 4) return false;
for(int i = 0; i < str.size(); i++)
{
if(str[i].size() == 0 || str[i][0] == '0' && str[i].size() >1 || str[i].size() > 3) return false;
int num = 0;
for(int j = 0; j < str[i].size(); j++)
{
char c = str[i][j];
if(c < '0' || c > '9') return false;
num = num * 10 + (c - '0');
if(num > 255) return false;
}
}
return true;
}
bool isIPv6(string IP)
{
if(IP.size() < 15 || IP[0] == ':' || IP[IP.size() - 1] == ':') return false;
vector<string > str = split(IP, ":");
if(str.size() != 8) return false;
for(int i = 0; i < str.size(); i++)
{
if(str[i].size() == 0 || str[i].size() > 4) return false;
for(int j = 0; j < str[i].size(); j++)
{
char c = str[i][j];
if(!((c >='a' && c <= 'f') || (c >='A' && c <= 'F') || (c >='0' && c <= '9'))) return false;
}
}
return true;
}
string solve(string IP) {
// write code here
if(isIPv4(IP)) return "IPv4";
if(isIPv6(IP)) return "IPv6";
return "Neither";
}
};
C++ 解法, 执行用时: 2ms, 内存消耗: 416KB, 提交时间: 2021-10-03
class Solution {
public:
/**
* 验证IP地址
* @param IP string字符串 一个IP地址字符串
* @return string字符串
*/
vector<string> split(string s,string spliter)
{
vector<string> ans;
int it;
while((it = s.find(spliter)) && it != s.npos)
{
ans.push_back(s.substr(0,it));
s = s.substr(it + 1);
}
ans.push_back(s);
return ans;
}
bool isIPv4(string IP)
{
///长度小于7开头或结尾为.都返回false
if(IP.size() < 7 || IP[0] == '.' || IP[IP.size() - 1] == '.')
return false;
//按照.切分
vector<string> str = split(IP,".");
//切割后的长度不够4返回false
if(str.size() != 4) return false;
for(int i = 0;i < str.size();i++)
{
//开头第一个不能是0
if(str[i].size() == 0 || str[i][0] == '0' && str[i].size() > 1 || str[i].size() > 3)
return false;
int num = 0;//转换数字
for(int j = 0; j < str[i].size();j++)
{
char c = str[i][j];
//必须是数字
if(c < '0' || c > '9')
return false;
//变化数字
num = num * 10 + (c - '0');
//范围0-255,不能超过255
if(num > 255)
return false;
}
}
return true;
}
bool isIPv6(string IP)
{
//特殊情况
if(IP.size() < 15 || IP[0] == ':' || IP[IP.size() - 1] == ':')
return false;
//按照.切分
vector<string> str = split(IP, ":");
//切割后的长度不够8返回false
if(str.size() != 8) return false;
for(int i = 0; i < str.size();i++)
{
if(str[i].size() == 0 || str[i].size() > 4)
return false;
for(int j = 0;j < str[i].size();j++)
{
char c = str[i][j];
///必须是数字或字母
if(!((c >= 'a' && c <= 'f') || (c >= 'A' && c <= 'F') || (c >= '0' && c <= '9')))
return false;
}
}
return true;
}
string solve(string IP) {
// write code here
if(isIPv4(IP)) return "IPv4";
if(isIPv6(IP)) return "IPv6";
return "Neither";
}
};
C++ 解法, 执行用时: 2ms, 内存消耗: 416KB, 提交时间: 2021-09-28
class Solution {
public:
/**
* 验证IP地址
* @param IP string字符串 一个IP地址字符串
* @return string字符串
*/
string solve(string IP) {
// write code here
if(IP.find('.') != IP.npos){
//可能为ipv4
int i = 0;
int points = 0;
while(i < (int)IP.size()){
if(isdigit(IP[i])){
if(IP[i] == '0' && isdigit(IP[i+1])){
return "Neither";
}else{
int n = 0;
while(isdigit(IP[i])){
n = 10*n + IP[i]-'0';
i++;
}//找到第一个非数字的位置
if(n > 255){
return "Neither";
}
}
}else{
if(IP[i] == '.'){
points ++;
}else{
return "Neither";
}
i++;
}
}
if(points == 3){
return "IPv4";
}
}
if(IP.find(':') != IP.npos){
//可能为IPV6
int i = 0, points = 0;
// vector<char> words = {'1','2','3','4','5','6','7','8','9','0','a','b','c','d','e','f'};
while(i < (int)IP.size()){
if(isdigit(IP[i]) || (IP[i] >='a' && IP[i] <='f') || (IP[i]>='A'&& IP[i]<='F')){
//找的到
int j = i;
while(isdigit(IP[j]) || (IP[j] >='a' && IP[j] <='f') || (IP[j] >='A' && IP[j]<='F')){
j++;
}
//j跳到了：或\0
// cout<<j<<endl;
if(j-i == 1){
// cout<<"i"<<IP[i]<<" j:"<<IP[j]<<endl;
if(IP[i] != '0'){
// cout<<"111"<<endl;
return "Neither";
}else{
i = j;
}
}else if(j-i == 4){
i = j;
}else{
// cout<<"222"<<endl;
return "Neither";
}
}else{
if(IP[i] == ':'){
points++;
i++;
}else{
// cout<<"333"<<endl;
return "Neither";
}
}
}
if(points == 7){
return "IPv6";
}else{
// cout<<"444"<<endl;
return "Neither";
}
}
return "Neither";
}
};
C 解法, 执行用时: 3ms, 内存消耗: 320KB, 提交时间: 2021-06-16
/**
* 验证IP地址
* @param IP string字符串 一个IP地址字符串
* @return string字符串
*/
#include<string.h>
char* solve(char* IP ) {
// write code here
int len = strlen(IP),flag = 0,num = 0;
for(int i = 0;i < len;i ++){
if(IP[i] == '.'){
flag = 4;
break;
}
if(IP[i] == ':'){
flag = 6;
break;
}
}
if(flag == 4){
for(int i = 0,j = 0;i < len;i ++){
if(IP[i] == '.'){
if(IP[j] == '0') return "Neither";
while(j < i){
num *= 10;
num += IP[j++] - '0';
}
if(num <= 0 || num >= 256) return "Neither";
num = 0;
j = i + 1;
}
}
return "IPv4";
}
if(flag == 6){
for(int i = 0,j = 0;i < len;i ++){
if(IP[i] == ':'){
if(i == j || i - j > 4) return "Neither";
while(j < i){
if(!((IP[j] >= '0' && IP[j] <= '9') || (IP[j] >= 'A' && IP[j] <= 'F') || (IP[j] >= 'a' && IP[j] <= 'f'))){
return "Neither";
}
j ++;
}
j = i + 1;
}
}
return "IPv6";
}
return "Neither";
}
)
，时间复杂度