#include <stdio.h>
#include <stdlib.h>
#include <string.h>
 
 
int main(void){
    system("cls");
 
    char str1[30] = "Good School";
    char str2[30] = "oo";
    char* s= str2;
    int count = 0;
 
    if(strstr(str1, str2)!= 0){
 
        printf("Tim thay");
    }
    else{
        printf("Khong tim thay");
    }
 
    for (int i = 0; i < strlen(str1); i++)
    {
        if (str1[i] == s )
        {
            count++;
        }
 
    }
    printf("\nStr2 xuat hien trong str1 %d lan", count);
}
 

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