{"id":1061,"date":"2024-10-19T13:26:45","date_gmt":"2024-10-19T07:56:45","guid":{"rendered":"https:\/\/codexplained.in\/?p=1061"},"modified":"2025-11-24T15:38:45","modified_gmt":"2025-11-24T10:08:45","slug":"count-number-of-digits","status":"publish","type":"post","link":"https:\/\/codexplained.in\/?p=1061","title":{"rendered":"Count Number of Digits"},"content":{"rendered":"
\n#include <stdio.h>\n\nint main() {\n    int number, count = 0;\n\n    \/\/ Prompt user for input\n    printf("Enter an integer: ");\n    scanf("%d", &number);\n\n    \/\/ Handle the case for 0 explicitly\n    if (number == 0) {\n        count = 1;\n    } else {\n        \/\/ Check if the number is negative\n        if (number < 0) {\n            number = -number;  \/\/ Convert to positive\n        }\n\n        \/\/ Count digits\n        while (number != 0) {\n            number \/= 10;  \/\/ Remove the last digit\n            count++;       \/\/ Increment count\n        }\n    }\n\n    \/\/ Display the result\n    printf("Number of digits: %d\\n", count);\n    return 0;\n}\n\n<\/pre><\/div>\n\n\n
Explanation:<\/h2>\n\n\n\n
Include the Standard I\/O Library<\/strong>:<\/p>\n\n\n\n
    \n
  • #include <stdio.h><\/code>: This line includes the standard input-output library necessary for using printf<\/code> and scanf<\/code> functions.<\/li>\n<\/ul>\n\n\n\n
    Main Function<\/strong>:<\/p>\n\n\n\n
      \n
    • int main()<\/code>: This is the entry point of the program. The program starts executing from this function.<\/li>\n<\/ul>\n\n\n\n
      Variable Declaration<\/strong>:<\/p>\n\n\n\n
        \n
      • int number, count = 0;<\/code>: We declare two integer variables:\n
          \n
        • number<\/code> will hold the user input.<\/li>\n\n\n\n
        • count<\/code> will keep track of the number of digits in the integer.<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n\n\n\n
          User Input<\/strong>:<\/p>\n\n\n\n
            \n
          • printf(\"Enter an integer: \");<\/code>: This line prompts the user to enter an integer.<\/li>\n\n\n\n
          • scanf(\"%d\", &number);<\/code>: This reads the integer input from the user and stores it in the number<\/code> variable.<\/li>\n<\/ul>\n\n\n\n
            Handling the Zero Case<\/strong>:<\/p>\n\n\n\n
              \n
            • The condition if (number == 0)<\/code> checks if the input is zero. Since zero has one digit, we set count<\/code> to 1 in this case.<\/li>\n<\/ul>\n\n\n\n
              Handling Negative Numbers<\/strong>:<\/p>\n\n\n\n
                \n
              • The condition if (number < 0)<\/code> checks if the number is negative. If it is, we convert it to positive by multiplying it by -1 (or simply using number = -number;<\/code>). This is important because the number of digits is the same for both positive and negative integers.<\/li>\n<\/ul>\n\n\n\n
                Counting Digits<\/strong>:<\/p>\n\n\n\n
                  \n
                • The while (number != 0)<\/code> loop runs as long as number<\/code> is not zero. Inside the loop:\n
                    \n
                  • number \/= 10;<\/code>: This line removes the last digit from the number by performing integer division. For example, if number<\/code> is 123, it becomes 12.<\/li>\n\n\n\n
                  • count++;<\/code>: Each time we remove a digit, we increment the count<\/code> variable.<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n\n\n\n
                    Display the Result<\/strong>:<\/p>\n\n\n\n
                      \n
                    • printf(\"Number of digits: %d\\n\", count);<\/code>: Finally, we print the number of digits counted.<\/li>\n<\/ul>\n\n\n\n
                      Return Statement<\/strong>:<\/p>\n\n\n\n
                        \n
                      • return 0;<\/code>: This indicates that the program has executed successfully.<\/li>\n<\/ul>\n\n\n\n
                        OUTPUT<\/h2>\n\n\n\n
                        Enter an integer: 12345<\/p>\n\n\n\n
                        Number of digits: 5<\/p>\n