안녕하세요 프로그래밍 초보자입니다 (_ _)

terms.txt 문서에서 사전식 검색이 가능한 간단한 프로그램인데요..

코딩들이 어떤과정들을 거쳐서 이러한 결과값이 나왔나 단어검색 프로그램의 논리 흐름을 알고싶습니다.

코딩 옆에 주석처럼 달아주셔서 알려주시면 감사하겠습니다!!



#include<stdio.h>
#include<string.h>
#include<conio.h>
#include<windows.h>
 
char terms[50][40];
char *file_name=\"terms.txt\";
void load_data(int *number);
void search_data(char data[][40], int number);
void sort_data(char data[][40], int number);
void upper_to_lower(char str[]);
void gotoxy(int x, int y);
 
int main(void)
{
        int number;
        load_data(&number);
        sort_data(terms, number);
        search_data(terms, number);
        return 0;
}
 
void search_data(char data[][40], int number)
{
        char input[40] = {\'\\0\'}, temp[40]={\'\\0\'};
        int i, length, count1=0, count2=0;
        do
        {
               gotoxy(1,1);
               printf(\"용어입력>\");
               length=strlen(input);
               gotoxy(11+length,1);
               input[count1]=getch();
               system(\"cls\");
               gotoxy(11,1);
               printf(\"%s\", input);
               gotoxy(1,3);
               count2=0;
 
               for(i=0; i<number; i++)
               {
                       strcpy(temp, data[i]);
                       upper_to_lower(temp);
                       if(strncmp(temp, input, count1+1)==0)
                       {
                              printf(\"%-40s\\n\", data[i]);
                              count2++;
                              if(count2>5)
                                      break;
                       }
               }
               if(input[count1]==27)
                       break;
               count1++;
        }while(1);
}
 
void sort_data(char data[][40], int number)
{
        int i,j,min;
        char temp1[39], temp2[39];
        for(i=0; i<number-1; i++)
        {
               min =i;
               for(j=i+1; j<number; j++)
               {
                       strcpy(temp1, data[j]);
                       strcpy(temp2, data[min]);
                       upper_to_lower(temp1);
                       upper_to_lower(temp2);
                       if(strcmp(temp1, temp2)<=0)
                              min=j;
               }
               strcpy(temp1, data[min]);
               strcpy(data[min], data[i]);
               strcpy(data[i], temp1);
        }
}
void gotoxy(int x, int y)
{
 
        COORD Pos = {x-1, y-1};
    SetConsoleCursorPosition(GetStdHandle(STD_OUTPUT_HANDLE), Pos);
 
}
 
void load_data(int *number)
{
        FILE *fp;
        *number=0;
        fp=fopen(file_name, \"r\");
        if(fp==NULL)
        {
               printf(\"file open error!\\n\");
               exit(1);
        }
        while(!feof(fp))
        {
               fgets(terms[*number], 39, fp);
               (*number)++;
        }
        fclose(fp);
 
}
void upper_to_lower(char str[])
{
        int i, length;
        length=strlen(str);
        for(i=0;i<length; i++)
               str[i]=tolower(str[i]);
}