Bài tập chuỗi trong C++

#include <iostream>
using namespace std;
  
int main() {
    char name[50];
    // doc chuoi tu ban phim
    cout << "Nhap chuoi: "; gets(name);
    // hien thi chuoi
    cout << "Chuoi ban nhap la: " << name << endl;
    return 0;
}

#include <iostream>
using namespace std;
  
int main() {
   // khoi tao chuoi s1
   char s1[] = "eLib.VN";
   int i = 0;
      
   // su dung vong lap while tinh do dai cua chuoi
   // '\0' la ky tu NULL ket thuc cua mot chuoi
   while(s1[i] != '\0') {
      i++;
   }
     
   cout << "Do dai cua chuoi " << s1 << " la: " << i << endl;
     
   return 0;
}

#include <iostream>
#include<string.h>
using namespace std;

int main() {
   char str[100];
   int len;
   
   cout << "\nNhap mot chuoi bat ky: ";
   gets(str);
   
   len = strlen(str);
   
   cout << "\nDo dai cua chuoi la: " << len << endl;
   return(0);
}

#include <stdio.h>

int main() {
   char s1[] = "eLib.VN";    // khai bao mot chuoi
   char s2[10];                  // bien de luu chuoi sao chep

   int length = 0;

   // sao chep chuoi s1
   while(s1[length] != '\0') {
      s2[length] = s1[length];
      length++;
   }

   s2[length] = '\0';        // gia tri null, ket thuc chuoi

   printf("Chuoi s1 = %s \n", s1);
   printf("Chuoi s2 = %s \n", s2);

   return 0;
}

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

int main() {
   char str1[100];
   char str2[100];
  
   printf("Nhap chuoi str1: ");
   gets(str1);
  
   strcpy(str2, str1);
   printf("\nChuoi sao chep la: %s", str2);
  
   return (0);
}

#include <stdio.h>
#include <string.h>
  
int main() {
   char s1[] = "VietTuts hoc lap trinh online, hoc c, hoc c++, hoc java, ...";
   char s2[] = "hoc";
  
   int n = 0;
   int m = 0;
   int times = 0;
   // bien luu giu do dai cua chuoi can tim kiem
   int len = strlen(s2);
  
   while(s1[n] != '\0') {
  
      if(s1[n] == s2[m]) {    // neu ky tu dau tien la giong nhau
  
         // tiep tuc tim kiem
         while(s1[n] == s2[m]  && s1[n] !='\0') {
            n++;
            m++;
         }
  
         // Neu day ky tu nay co do dai bang chuoi tim kiem
         if(m == len && (s1[n] == ' ' || s1[n] == '\0')) {
  
            // Chuc mung ban da tim ra chuoi can tim
            times++;
         }
      } else {   // Neu ky tu dau tien khong giong nhau
         while(s1[n] != ' ') {    //bo qua, tiep tuc tim kiem tu tiep theo
            n++;
            if(s1[n] == '\0')
            break;
         }
      }
          
      n++;
      m=0;  // reset bien dem.
   }

   printf("Chuoi ban dau: %s", s1);
   if(times > 0) {
      printf("\nChuoi '%s' xuat hien %d lan\n", s2, times);
   }else {
      printf("\nChuoi '%s' khong xuat hien trong cau.\n", s2);
   }
  
   return 0;
}