strcmp() issue

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

int main(int argc, char** argv) {

    FILE *inp; /* pointer to input file */
    FILE *outp; /* pointer to ouput file */
    char arr_w[50][50];
    char c;
    int word_count = 0;
    int char_count = 0;


    /* Prepare files for input or output */
    inp = fopen("in_file.txt", "r");

    //Reading whole words
    if (inp) {
        while ((c = fgetc(inp)) != EOF) {
           if (c == ' ' || c == '\n') {
               //printf("\n");

               arr_w[word_count][char_count] = '\0'; //Terminate the string
               char_count = 0; //Reset the counter.
               word_count++;
           }
           else {
               arr_w[word_count][char_count] = c;
               //printf("%c",arr_w[word_count][char_count]);

               if (char_count < 19) {
                   char_count++;
               }
               else {
                   char_count = 0;
               }
           }
       }
    }
    else {
        printf("File does not exit\n");
    }

    printf("word count: %d\n", word_count+1);
    for (int i = 0; i <word_count; i++) {
        if (strcmp(arr_w[i], "mark") == 0) {
            printf("%s found at index %d \n", arr_w[i], i);
        }
    }
}

//////
Output:
word count: 3

/////

in_file.txt:
mark
john
bob