#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#define MAX 100
//ham kien tra ky tu xuat hien trong chuoi va lan xuat hien
int ktXuatHien(char a[], char s){
    int dem = 0;
    for (int i = 0; i < strlen(a) / 2; i++)
    {
        if (a[i] == s)
        {
            dem++;
        }
    }  
    if (dem > 0)
    {
        printf("Ky tu '%c' co xuat hien trong chuoi va xuat hien %d lan.", s, dem);
    }else{
        printf("Ky tu '%c' khong xuat hien trong chuoi.", s);
    }
 
}
int main(){
    system("cls");
 
    char a[MAX], s;
    printf("nhap vao chuoi: ");
    gets(a);
    printf("Nhap vao ky tu cau tim: ");
    scanf("%c", &s);
 
    ktXuatHien(a, s);
    return 0;
}
 

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