exercises and solutions

C programming :
C variables and datatypes exercises:

Exercise 1: Write a C program to print the following lines:

You are 10 years old. 
You are too young to play the game

 Solution: 

#include <stdio.h> 
#include <stdlib.h> 
  
int main(int argc, char *argv[]) 
{ 
  int age; 
  age=10; 
  printf(" You are %2d ",age);printf("years old.\n"); 
  printf(" You are too young to play the game.\n"); 
  
  system("PAUSE");      
  return 0; 
}  

Exercise 2: Write five statements to print the asterisk pattern:

***** 
***** 
***** 
***** 
*****

Solution: 
#include <stdio.h> 
#include <stdlib.h> 
  
int main(int argc, char *argv[]) 
{ 
    printf("*****\n"); 
    printf("*****\n"); 
    printf("*****\n"); 
    printf("*****\n"); 
    printf("*****\n"); 
    system("PAUSE"); 
    return EXIT_SUCCESS; 
}

Exercise 3:  Write a C program to declare two integer and one float variables then initialize them to 10, 15, and 12.6. It then prints these values on the screen.

Solution: 

#include <stdio.h> 
#include <stdlib.h> 
  
int main(int argc, char *argv[]) 
{ 
    int x; 
    int y; 
    float z; 
    x=10; 
    y=15; 
    z=12.6; 
    printf("x= %d",x);printf("\t"); 
    printf("y=%d",y);printf("\t"); 
    printf("z=%3.1f",z); 
    printf("\n"); 
  
  system("PAUSE");      
  return 0; 
}

Exercise 4:  Write a C program to prompt the user to input her/his age and print it on the screen, as shown below.

Your age is 20 years old.

Solution: 
#include <stdio.h> 
#include <stdlib.h> 
  
int main
{ 
    int age; 
    printf("Enter your age:"); 
    scanf("%d",&age); 
    printf("You are %2d ",age);printf(" years old.\n"); 
  
    system("PAUSE");    
    return 0; 
}

Exercise 5:  Write a C program to prompt the user to input 3 integer values and print these values in forward and reversed order, as shown below.

  
Please enter your 3 numbers: 12 45 78 
  
Your numbers forward: 
12 
45 
78 
  
Your numbers reversed: 
78 
45 
12

Solution: 
#include <stdio.h> 
#include <stdlib.h> 
  
int main(int argc, char *argv[]) 
{ 
    int val1; 
    int val2; 
    int val3; 
    printf("Please enter your 3 numbers:"); 
    scanf("%d %d %d",&val1,&val2,&val3); 
    
    printf("\nYour numbers forward:\n"); 
    printf("%d",val1);printf("\n"); 
    printf("%d",val2);printf("\n"); 
    printf("%d",val3);printf("\n"); 
    printf("Your numbers reversed:\n"); 
    printf("%d",val3);printf("\n"); 
    printf("%d",val2);printf("\n"); 
    printf("%d",val1);printf("\n"); 
  
    system("PAUSE");    
    return 0; 
} 

C exercises - conditional statements:

1. Write a C code that prompts the user to input tree integer values and find the greatest value of the three values.

Example: 
Enter 3 integer vales separated by space: 10 15 20 
The greatest value is: 20
Solution: 
#include <stdio.h> 
#include <stdlib.h> 
  
int main
{ 
    
   int x, y, z, max; 
   printf("Enter 3 integer vales separated by space:"); 
   scanf("%d %d %d",&x,&y,&z); 
   max=x;    if(max<y) max=y;    if(max<z) max=z;     printf("The max is %d.",max);  
   printf("\n"); 
   
   system("PAUSE");   
   return 0; 
}

2. Write a program that determines a student’s grade. The program will read three scores and determine the grade based on the following rules:

-if the average score =90% =>grade=A 
-if the average score >= 70% and <90% => grade=B 
-if the average score>=50% and <70% =>grade=C 
-if the average score<50% =>grade=F
Solution: 
#include <stdio.h> 
#include <stdlib.h> 
  
int main(int argc, char *argv[]) 
{ 
    
    
   float x; 
   float y; 
   float z; 
   float avg; 
   printf("Enter 3 score vales separated by space:"); 
   scanf("%f %f %f",&x,&y,&z); 
   avg=(x+y+z)/3; 
        
   if(avg>=90)printf("Grade A"); 
   else if((avg>=70) && (avg<90)) printf("Grade B"); 
   else if((avg>=50) && (avg<70))printf("Grade C"); 
   else if(avg<50) printf("Grade F"); 
   else printf("Invalid"); 
    
   printf("\n"); 
  
   system("PAUSE");   
   return 0; 
} 

Loops in C exercises:

1. Write a C program that will print the following pattern

******* 
****** 
***** 
**** 
*** 
** 
* 

Solution: 
#include <stdio.h> 
#include <stdlib.h> 
int main 
{ 
 int i=7; 
 int j=7; 
  
 for(i=1;i<=7;i++){ 
  for(j=7-i;j>=1;--j)printf("*"); 
  printf("\n"); 
} 
   
   printf("\n"); 
   system("PAUSE"); 
   return EXIT_SUCCESS; 
}

2. Write a C program that will print the following pattern:

       1****** 
       12***** 
       123**** 
       1234*** 
       12345** 
       123456* 
       1234567
Solution: 
#include <stdio.h> 
#include <stdlib.h> 
  
int main
{ 
 int i; 
 int j; 
 int k; 
  
 for(i=1;i<=7;i++){ 
  for(j=1;j<=i;++j) 
    cout<<j;                
                
  for(k=7-i;k>=1;k--) printf("*");                 
   
  printf("\n"); 
} 
   
   printf("\n"); 
   system("PAUSE"); 
   return EXIT_SUCCESS; }