{"id":796,"date":"2025-11-21T08:53:52","date_gmt":"2025-11-21T03:23:52","guid":{"rendered":"https:\/\/codexplained.in\/?p=796"},"modified":"2025-11-21T08:53:52","modified_gmt":"2025-11-21T03:23:52","slug":"count-words-in-a-sentence","status":"publish","type":"post","link":"https:\/\/codexplained.in\/?p=796","title":{"rendered":"Count Words in a Sentence"},"content":{"rendered":"
\n#include <stdio.h>\n#include <ctype.h>\n\n\/\/ Function to count the words in a given sentence\nint countWords(char str[]) \n{\n    int count = 0;   \/\/ This will store the word count\n    int inWord = 0;  \/\/ This will check if we are inside a word (flag)\n\n    \/\/ Loop through each character of the string until we hit the null terminator ('\\0')\n    for (int i = 0; str[i] != '\\0'; i++) \n{\n        \/\/ Check if the current character is a space or punctuation (i.e., word separator)\n        if (isspace(str[i])) \n{\n            inWord = 0; \/\/ We are outside a word now\n        } \nelse if (inWord == 0) \n{\n            \/\/ We've encountered a non-space character (a new word)\n            inWord = 1; \/\/ Set flag to indicate we're inside a word\n            count++;    \/\/ Increment the word count\n        }\n    }\n    return count; \/\/ Return the total word count\n}\n\nint main() \n{\n    char sentence[100]; \/\/ Array to store the sentence\n    printf("Enter a sentence: ");\n    fgets(sentence, sizeof(sentence), stdin); \/\/ Input sentence from the user\n\n    \/\/ Call the countWords function and display the result\n    int wordCount = countWords(sentence);\n    printf("The number of words in the sentence: %d\\n", wordCount);\n    return 0;\n}\n\n<\/pre><\/div>\n\n\n
Explanation:<\/h3>\n\n\n\n
    \n
  1. Libraries<\/strong>:\n
      \n
    • We include the stdio.h<\/code> library for input and output functions like printf<\/code> and fgets<\/code>.<\/li>\n\n\n\n
    • The ctype.h<\/code> library is used to work with character functions like isspace()<\/code>, which checks if a character is a space or a whitespace.<\/li>\n<\/ul>\n<\/li>\n\n\n\n
    • Function: countWords<\/code><\/strong>:\n
        \n
      • This function takes a string (char str[]<\/code>) and loops through each character to count words.<\/li>\n\n\n\n
      • We maintain two variables: count<\/code> to keep track of the number of words, and inWord<\/code> to check if we are currently inside a word.<\/li>\n\n\n\n
      • The loop checks if the current character is a space or not. If it’s not a space and we aren’t already inside a word, we count it as the start of a new word.<\/li>\n<\/ul>\n<\/li>\n\n\n\n
      • Word Definition<\/strong>:\n
          \n
        • A word is defined as any sequence of characters separated by spaces or punctuation. So, the function counts words based on this condition.<\/li>\n<\/ul>\n<\/li>\n\n\n\n
        • Input Handling<\/strong>:\n
            \n
          • The user is prompted to input a sentence using fgets()<\/code>. This function is safer than gets()<\/code> as it prevents buffer overflows by limiting input to the size of the array.<\/li>\n<\/ul>\n<\/li>\n\n\n\n
          • Main Function<\/strong>:\n
              \n
            • The program calls the countWords()<\/code> function with the user’s input and displays the result.<\/li>\n<\/ul>\n<\/li>\n<\/ol>\n\n\n
              \nEnter a sentence: Hello world, this is a test sentence.\nThe number of words in the sentence: 7\n\n<\/pre><\/div>\n\n\n
              Input:<\/h4>\n\n\n\n
                \n
              • \"Hello world, this is a test sentence.\"<\/code><\/li>\n<\/ul>\n\n\n\n
                Explanation of Output:<\/h4>\n\n\n\n
                  \n
                • The input sentence has seven words: Hello<\/code>, world,<\/code>, this<\/code>, is<\/code>, a<\/code>, test<\/code>, sentence.<\/code>.<\/li>\n<\/ul>\n\n\n\n
                  <\/p>\n