파일에서 불러온 문장을 각각 배열에 넣고 배열간에 문자 비교하는법 도와주세요

 26     library_file = fopen("library.txt","r");
 27     if (library_file == NULL) {
 28         printf("file open error\n");
 29         return 0;
 30     }
 31     while (!feof(library_file)) {
 32         fgets(library_buf, max_size, library_file);
 33         library_len = strlen(library_buf);
 34
 35         source_file = fopen(file_name,"r");
 36         if (source_file == NULL) {
 37             printf("file open error\n");
 38             return 0;
 39         }
 40         while (!feof(source_file)) {
 41             fgets(source_buf, max_size, source_file);
 42             check_pt = source_buf;
 43             source_len = strlen(check_pt);
 44             while (source_len > library_len) {
 45                 check_pt = strstr(source_buf, library_buf);
 46                 if (check_pt != NULL) {
 47                     printf("%s\n",check_pt);
 48                 } else {
 49                     continue;
 50                 }
 51                 check_pt = check_pt + library_len;
 52                 source_len = strlen(check_pt);
 53             }
 54         }
 55         fclose(source_file);
 56     }
 57     fclose(library_file);
 58 }