Needle in the haystack. I'm a beginner in programming and we only learned a thing or two so far, barely reached arrays yet.

Input: 1 4325121
Output: 2

1. Input two values in one line. The first one shall accept any integer from 0-9 and the other one shall take a random positive integer.
2. Using a while loop, count how many of the first integer (0-9) is present in the digits of the second inputted integer and print the result.

No arrays to be used here, only while loops and else-if conditions with basic coding knowledge and without the use of advanced coding.

CodePudding user response：

As you said, you need to keep it as simple as possible. Then this can be a solution:

#include <iostream>

int main()
{
    int first { };
    int second { };

    std::cin >> first >> second;

    int quo { second };
    int rem { };
    int count { };

    while ( quo > 0 )
    {
        rem = quo % 10;
        quo /= 10;

        if ( first == rem  )
        {
              count;
        }
    }

    std::cout << "Result: " << count << '\n';
}

CodePudding user response：

Using while loop

    #include <iostream>
    using namespace std;

    int main()
    {
        int a = 1;
        int b = 4325121;
        int count = 0;
        while(b > 0)
        {
            int m = b % 10;
            if(m == a)
            {
                count  ;
            }
            b /= 10;
        }
        cout << count;
        return 0;
    }

CodePudding user response：

Nice little problem:

#include <iostream>
#include <sstream>
#include <iomanip>
#include <string>
using namespace std;

// this is from https://stackoverflow.com/questions/4654636/how-to-determine-if-a-string-is-a-number-with-c 
bool is_number(const string& s)
{
    string::const_iterator it = s.begin();
    while (it != s.end() && std::isdigit(*it))   it;
    return !s.empty() && it == s.end();
}

int main() {

  while (true) {
    cout << "Input, two integer numbers, first one single cipher:" << endl;
    // read line of inupt
    string input;
    std::getline(cin, input);
 
    // split it into two words
    string word1, word2;
    istringstream ss(input);
    ss >> word1 >> word2;

    // check if both are integers
    if (!is_number(word1) || !is_number(word2)) {
      cout << "Input must be two integer values!" << endl;
      continue;
    }
    
    // make sure first input is just single cipher from 0...9
    if (word1.size() != 1) {
      cout << "First input must be a single cipher from 0 to 9." << endl;     
      continue;
    }

    // now count
    int count = 0;
    for (char character : word2) {
      if (character == word1[0]) {  // this is a "char" vs "char" comparison
        count  ; 
      }
    } 

    cout << "Result:" << count << endl;
  }
  
  return 0;
}