Code

 Header...
// static demonstration

 double addup(double k){
»  static int called;
»  static double sum;

»  sum+=k;
»  printf("k is %g new sum is %f\n", k, sum);
»  printf("The function has been called %d times\n", ++called);

»  return sum;
}
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 int main(){
»  int i, max=5;
»  double mysum;

»  for (i=1; i<=max; ++i) 
    mysum=addup(sqrt(i));

»  printf("The sum of the square roots of 1 to %d is %g\n", 
         max, mysum);
»  return 0;
}
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