Exercise 3.38 - 3.40 (Deitel: C How to Program 6th Edition)

3.38 

Write a program that prints 100 asterisks, one at a time. After every tenth asterisk, your program should print a newline character. [Hint: Count from 1 to 100. Use the remainder operator to recognize each time the counter reaches a multiple of 10.]

C Program:

#include <stdio.h> 
int main(){    int a, b;
    for(a=0; a<=10; a++){
       for(b=0; b<=10; b++) {          printf("*");       }
       printf("\n");
    }
    system("pause");
}

Output:

3.39 (Counting 7s)

Write a program that reads an integer and determines and prints how many digits in the integer are 7s.

C Program:

#include <stdio.h>

int main(){
    int input, temp, sisa = 0, seven = 0;
    printf("Masukan angka: ");
    scanf("%d", &input);
    temp=input;
    while(temp!=0){
       sisa=temp%10;
       if(sisa==7) {seven++;}
       temp/=10;
    }
    printf("Jumlah angka 7 ada %d angka.\n", seven);
    system("pause");
}

Output:

3.40 (Checkerboard Pattern of Asterisks)

Write a program that prints 100 asterisks, one at a time.

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

int main()
{
int side =8;
int row;
int mod;while( side >=1) {
row =8;
mod = side %2;

while( row >=1) {
       if( mod !=0) {
printf(" ");mod =0;
}
printf("* ");
--row;
}
printf("\n");
--side;
}
system ("PAUSE");

Output: