Find first occurrence of a word in a string

Posted on Apr 21, 2020

C program to find first occurrence of a word in a given string.

Program

#include<stdio.h>
#include<conio.h>
#define MAX 50

int split_words(char str[MAX], char words[MAX][MAX])
{
    int i, j, count;
    char prev_char;

    i = 0;
    j = 0;
    count = 0;
    prev_char = '\0';

    while(1)
    {
        if(str[i] == ' ' || str[i] == '\t' || str[i] == '\0')
        {
            if(prev_char!=' ' && prev_char!='\t' && prev_char!='\0')
            {
                words[count][j] = '\0';
                count++;
                j = 0;
            }

        }
        else
        {
            words[count][j] = str[i];
            j++;
        }
        prev_char = str[i];
        if(str[i] == '\0')
            break;
        else
            i++;
    }

    return(count);
}

void main()
{
	char str[MAX], word[MAX];
    char words[MAX][MAX];
    int count, i, flag, index;

    printf("Enter the string\t:");
    gets(str);
    printf("Enter the word to be searched\t:");
    gets(word);

    count = split_words(str, words);
    flag = 0;
    index = 0;
    for(i=0;i<count;i++)
    {
        if(!strcmp(words[i],word))
        {
            flag = 1;
            break;
        }
        index = index + strlen(words[i]) + 1;
    }

    if(flag == 1)
    {
        printf("\nWord '%s' found at position %d",word,index+1);
    }
    else
    {
        printf("\nWord not found");
    }

    getch();	
}

Output

Enter the string        :come see come
Enter the word to be searched   :see

Word 'see' found at position 6