检查二进制字符串是否包含连续的相同

给定一个由字符'0'和'1'组成的二进制字符串str 。任务是查找字符串是否有效。字符串只有在字符交替出现时才有效，即没有两个连续字符相同。
例子：

Input: str[] = “010101” 
Output: Valid
Input: str[] = “010010” 
Output: Invalid 
 

方法：开始逐个字符遍历字符串，如果有任意两个连续的字符字符，则打印无效，否则最后打印有效。
下面是上述方法的实现：

C++

// C++ implementation of the approach
#include 
using namespace std;
 
// Function that returns true is str is valid
bool isValid(string str, int len)
{
 
    // Assuming the string is binary
    // If any two consecutive characters are equal
    // then the string is invalid
    for (int i = 1; i < len; i++) {
        if (str[i] == str[i - 1])
            return false;
    }
 
    // If the string is alternating
    return true;
}
 
// Driver code
int main()
{
    string str = "0110";
    int len = str.length();
 
    if (isValid(str, len))
        cout << "Valid";
    else
        cout << "Invalid";
 
    return 0;
}

Java

// Java implementation of the approach
class gfg
{
     
// Function that returns true is str is valid
static boolean isValid(String str, int len)
{
 
    // Assuming the string is binary
    // If any two consecutive
    // characters are equal
    // then the string is invalid
    for (int i = 1; i < len; i++)
    {
        if (str.charAt(i) == str.charAt(i - 1))
            return false;
    }
 
    // If the string is alternating
    return true;
}
 
// Driver code
public static void main(String[] args)
{
    String str = "0110";
    int len = str.length();
 
    if (isValid(str, len))
        System.out.println("Valid");
    else
        System.out.println("Invalid");
}
}
 
// This code is Contributed by Code_Mech

Python3

# Python3 implementation of the approach
 
# Function that returns true is str is valid
def isValid(string, length):
 
    # Assuming the string is binary
    # If any two consecutive characters
    # are equal then the string is invalid
    for i in range(1, length):
        if string[i] == string[i - 1]:
            return False
 
    # If the string is alternating
    return True
 
# Driver code
if __name__ == "__main__":
 
    string = "0110"
    length = len(string)
 
    if isValid(string, length):
        print("Valid")
    else:
        print("Invalid")
 
# This code is contributed by Rituraj Jain

C#

// C# implementation of the approach
using System;
 
class gfg
{
     
// Function that returns true is str is valid
static bool isValid(string str, int len)
{
 
    // Assuming the string is binary
    // If any two consecutive
    // characters are equal
    // then the string is invalid
    for (int i = 1; i < len; i++)
    {
        if (str[i] == str[i - 1])
            return false;
    }
 
    // If the string is alternating
    return true;
}
 
// Driver code
public static void Main()
{
    string str = "0110";
    int len = str.Length;
 
    if (isValid(str, len))
        Console.Write("Valid");
    else
        Console.Write("Invalid");
}
}
 
// This code is contributed by Ita_c.

Javascript

// Javascript implementation of the approach
 
// Function that returns true is str is valid
function isValid(str,len)
{
    // Assuming the string is binary
    // If any two consecutive
    // characters are equal
    // then the string is invalid
    for (let i = 1; i < len; i++)
    {
        if (str[i] == str[i - 1])
            return false;
    }
   
    // If the string is alternating
    return true;
}
 
// Driver code
let str = "0110";
let len = str.length;
 
if (isValid(str, len))
    document.write("Valid");
else
    document.write("Invalid");
 
 
// This code is contributed by rag2127

输出：

Invalid