5.2

I.Lý Thuyết
Định nghĩa ...Là một chuỗi kí tự kết thúc bằng kí tự NULL
Định Nghĩa không thể bịa nên em chỉ chép đúng như những lời cô giảng :-ss
II-Bài Tập.
Bài 1 :

Write a program which prints the letters in a char array in reverse order. For

example, if the array contains {'c', 's', 'c', '2', '6', '1'}the output (to the terminal)

should be "162csc"

#include <stdio.h>
#include <stdlib.h>

/* run this program using the console pauser or add your own getch, system("pause") or input loop */

int main(int argc, char *argv[]) {
    char a[6]={'c','s','c','2','6','1'};
    int i;
    for(i=5;i>=0;i--)
    printf("\ta[%d]=%c",i,a[i]);
    return 0;
}
Bài 2 :

Write a  program : declare a char array and the size of the array (of type char). This function counts the number of digit letters in the char array.

char a[30];
int i,j=0;
printf("Nhap Chuoi Ki Tu :");
scanf("%c",&a);

for (i=0;i<30;i++)
if (a[i] != 0)

j++;
printf("so ki tu trong chuoi la: %d",j-5);

return 0;

Bài 3 :

Write a program that counts the number of words in a string

 #include <stdio.h>
#include <stdlib.h>

/* Write a program that counts the number of words in a string */

int main(int argc, char *argv[]) {
char a[30];
int i,j;
printf("Nhap Chuoi: ");
scanf("%c",&a);
j=1;
for(i=0;i<30;i++) if (a[i]==' ') j=j+1;
printf("So Tu: %d ",j);

return 0;
}

Bài 4:

Write a program that accept two string, after checking if string1 equals string2 then print 'string 1 equals string2', else print string1 less than or greater than string 2.

#include <stdio.h>
#include <stdlib.h>

/* Write a program that counts the number of words in a string */

int main(int argc, char *argv[]) {
char a[30];
char b[30];
printf("Nhap Chuoi: ");
scanf("%c",&a);
printf("Nhap Chuoi : ");
scanf("%c",&b);
if(a,b==0){

printf("a va b bang nhau");}

else {
printf("a va b khong bang nhau");

}

return 0;
}

Bài 5 :

Write a function that scans a character array for the character - and replaces it with _

 
  #include <stdio.h>
#include <stdlib.h>

/* Write a program that counts the number of words in a string */

int main(int argc, char *argv[]) {
char a[30];
int i;
printf("Nhap Chuoi: ");
scanf("%s",&a);
for(i=0;i<30;i++){
if(a[i]=='-')
a[i]='_';
}
printf("%s",a);

return 0;
}