给定数字在数字中的位置值

可以将位置值定义为根据其在数字中的位置，用数字中的数字表示的值。这是带有示例的位置值说明：

让我们再举一个例子来说明N = 45876的位置值

问题：
给定正整数N和数字D。任务是找出给定数字N中的数字D的位置值。如果多次出现数字，则找到最小位数。

例子：

Input: N = 3928, D = 3
Output: 3000
Explaination:
Place value of 3 in this number is 3*1000 = 3000

Input: N = 67849, D = 6
Output: 60000

解决方法：

1. 从输入数字的右侧找到数字的位置。为了找到位置，将那个数字的mod乘以10，然后检查该数字，然后将该数字除以10。
2. 找到数字的位置后，只需将数字乘以10的^位置即可。

这是上述方法的实现：

C++

// C++ implementation to find
// place value of a number
#include
using namespace std;
  
// Function to find place value
int placeValue(int N, int num)
{
    int total = 1, value = 0, rem = 0;
    while (true)
    {
        rem = N % 10;
        N = N / 10;
  
        if (rem == num)
        {
            value = total * rem;
            break;
        }
        total = total * 10;
    }
    return value;
}
  
// Driver Code
int main()
{
  
    // Digit, which we want
    // to find place value.
    int D = 5;
  
    // Number from where we
    // want to find place value.
    int N = 85932;
  
    cout << (placeValue(N, D));
}
  
// This code is contributed by Ritik Bansal

Java

// Java implementation to find
// place value of a number
  
import java.util.*;
import java.io.*;
import java.lang.*;
  
class GFG {
  
    // function to find place value
    static int placeValue(int N, int num)
    {
        int total = 1, value = 0, rem = 0;
        while (true) {
            rem = N % 10;
            N = N / 10;
  
            if (rem == num) {
                value = total * rem;
                break;
            }
  
            total = total * 10;
        }
        return value;
    }
  
    // Driver Code
    public static void main(String[] args)
    {
  
        // Digit, which we want
        // to find place value.
        int D = 5;
  
        // Number from where we
        // want to find place value.
        int N = 85932;
  
        System.out.println(placeValue(N, D));
    }
}

Python3

# Python3 implementation to find 
# place value of a number 
  
# Function to find place value 
def placeValue(N, num): 
      
    total = 1
    value = 0
    rem = 0
      
    while (True): 
        rem = N % 10
        N = N // 10
  
        if (rem == num): 
            value = total * rem 
            break
        total = total * 10
          
    return value 
  
# Driver Code
  
# Digit, which we want 
# to find place value. 
D = 5
  
# Number from where we 
# want to find place value. 
N = 85932
  
print(placeValue(N, D))
  
# This code is contributed by divyamohan123

C#

// C# implementation to find
// place value of a number
using System;
class GFG{
  
// function to find place value
static int placeValue(int N, int num)
{
    int total = 1, value = 0, rem = 0;
    while (true) 
    {
        rem = N % 10;
        N = N / 10;
  
        if (rem == num) 
        {
            value = total * rem;
            break;
        }
  
        total = total * 10;
    }
    return value;
}
  
// Driver Code
public static void Main()
{
  
    // Digit, which we want
    // to find place value.
    int D = 5;
  
    // Number from where we
    // want to find place value.
    int N = 85932;
  
    Console.Write(placeValue(N, D));
}
}
  
// This code is contributed by Code_Mech

输出：

5000

时间复杂度： O(log N)
辅助空间： O(1)