Language: C

#include<stdio.h>

unsigned short scan_sentence(unsigned char * str, unsigned short length_max);
void count_alphabet(unsigned char * str, unsigned short * num_check, unsigned short length);

int main(){

	unsigned short length;#include<stdio.h>

unsigned short scan_sentence(unsigned char * str, unsigned short length_max);
void count_alphabet(unsigned char * str, unsigned short * num_check, unsigned short length);

int main(){

	unsigned short usW_D_length;
	unsigned char ubW_D_str[1200];
	unsigned short usW_D_num_check[26];
	unsigned short usW_C_i;
	
	for(usW_C_i = 0;usW_C_i < 1200;usW_C_i++){
		ubW_D_str[usW_C_i] = 0;
	}
	for(usW_C_i = 0;usW_C_i < 26;usW_C_i++){
		usW_D_num_check[usW_C_i] = 0;
	}
	
	usW_D_length = scan_sentence(ubW_D_str, 1200);
	
	count_alphabet(ubW_D_str, usW_D_num_check, usW_D_length);
	
	for(usW_C_i = 0;usW_C_i < 26;usW_C_i++){
		printf("%c : %d\n", (usW_C_i + 97), *(usW_D_num_check + usW_C_i));
	}
	
	return 0;
}

/* 関数名：文字列入力 */
/* 概要：文字列を入力する。その長さを返す */
/* 引数：文字列を格納する配列の先頭アドレス、その配列の大きさ */
/* 戻り値：入力された文字列の長さ */
unsigned short scan_sentence(unsigned char * str, unsigned short length_max)
{
	unsigned short count_text = 0;
	unsigned short usW_C_i;

	for(usW_C_i = 0;usW_C_i < length_max;usW_C_i++){
		scanf("%c", str + usW_C_i);
		if(*(str + usW_C_i) == EOF){
			break;
		}
		count_text++;
	}

	return count_text;
}

/* 関数名：アルファベットカウント */
/* 概要：渡された文字列に各アルファベットが何文字含まれるか調べる */
/* 引数：文字列が格納された配列の先頭アドレス、アルファベットの数を記録する配列の先頭アドレス、文字列の長さ */
/* 戻り値：なし */
void count_alphabet(unsigned char * str, unsigned short * num_check, unsigned short length)
{
	unsigned short usW_C_i;
	char alphabet;
	for(usW_C_i = 0;usW_C_i < length;usW_C_i++){
		if(((65 <= *(str + usW_C_i)) && (*(str + usW_C_i) <= 90)) || ((97 <= *(str + usW_C_i)) && (*(str + usW_C_i) <= 122))){
			alphabet = *(str + usW_C_i) & 0x1F;
			*(num_check + (alphabet - 1)) += 1;
		}
	}
}


	unsigned char str[1200];
	unsigned short num_check[26];
	unsigned short i;
	
	for(i = 0;i < 1200;i++){
		str[i] = 0;
	}
	for(i = 0;i < 26;i++){
		num_check[i] = 0;
	}
	
	length = scan_sentence(str, 1200);
	
	count_alphabet(str, num_check, length);
	
	for(i = 0;i < 26;i++){
		printf("%c : %d\n", (i + 97), *(num_check + i));
	}
	
	return 0;
}

/* 関数名：文字列入力 */
/* 概要：文字列を入力する。その長さを返す */
/* 引数：文字列を格納する配列の先頭アドレス、その配列の大きさ */
/* 戻り値：入力された文字列の長さ */
unsigned short scan_sentence(unsigned char * str, unsigned short length_max)
{
	unsigned short count_text = 0;
	unsigned short i;

	for(i = 0;i < length_max;i++){
		scanf("%c", str + i);
		if(*(str + i) == EOF){
			break;
		}
		count_text++;
	}

	return count_text;
}

/* 関数名：アルファベットカウント */
/* 概要：渡された文字列に各アルファベットが何文字含まれるか調べる */
/* 引数：文字列が格納された配列の先頭アドレス、アルファベットの数を記録する配列の先頭アドレス、文字列の長さ */
/* 戻り値：なし */
void count_alphabet(unsigned char * str, unsigned short * num_check, unsigned short length)
{
	unsigned short i;
	char alphabet;
	for(i = 0;i < length;i++){
		if(((65 <= *(str + i)) && (*(str + i) <= 90)) || ((97 <= *(str + i)) && (*(str + i) <= 122))){
			alphabet = *(str + i) & 0x1F;
			*(num_check + (alphabet - 1)) += 1;
		}
	}
}




Compiler output:
main.c: In function 'main':
main.c:8:31: error: stray '#' in program
    8 |         unsigned short length;#include<stdio.h>
      |                               ^
main.c:8:32: error: 'include' undeclared (first use in this function)
    8 |         unsigned short length;#include<stdio.h>
      |                                ^~~~~~~
main.c:8:32: note: each undeclared identifier is reported only once for each function it appears in
main.c:8:40: error: 'stdio' undeclared (first use in this function); did you mean 'stdin'?
    8 |         unsigned short length;#include<stdio.h>
      |                                        ^~~~~
      |                                        stdin
main.c:10:1: error: expected expression before 'unsigned'
   10 | unsigned short scan_sentence(unsigned char * str, unsigned short length_max);
      | ^~~~~~~~
main.c:62:6: error: static declaration of 'count_alphabet' follows non-static declaration
   62 | void count_alphabet(unsigned char * str, unsigned short * num_check, unsigned short length)
      |      ^~~~~~~~~~~~~~
main.c:11:6: note: previous declaration of 'count_alphabet' with type 'void(unsigned char *, short unsigned int *, short unsigned int)'
   11 | void count_alphabet(unsigned char * str, unsigned short * num_check, unsigned short length);
      |      ^~~~~~~~~~~~~~