Push Ups withBlaze

• Problem Description

  
  At UAB football games, Blaze does push ups after each Blazer score. After the first Blazer touchdown (and point after), Blaze does 7 push ups. After the second touchdown and point after, the score is now 14 and Blaze does 14 push ups.
  
  Write a program that calculates how many total push ups Blaze does during the whole game. Assume that only 7 point touchdowns (including the point after) occur. Prompt for the final score and print out how many push ups Blaze has done.
  

• Test Case 1

  
  Input (stdin)

  21
  
  

  Expected Output

  42

• Test Case 2

  
  Input (stdin)

  28
  
  

  Expected Output

  70

• Program

• #include <stdio.h>
  int main()
  {
     int a,b,i;
    scanf("%d",&a);
    for(i=7;i<=a;i=i+7)
      b=b+i;
    printf("%d",b);
      
   return 0;
  }