Explain the purpose of using the RunOnce variable in the following function:

void

DisplayMenu(void)

{

static

int RanOnce = 0;

printf("Main Menu\

n ");

printf("1. Calculate Average Temperature\

n");

printf("2. Calculate Frequency of Variables\

n");

printf("3. Calculate Mean Temperature\

n");

printf("4. Determine Max and Min Temperature

");

if(RanOnce) printf("5. Reinitialize values ");

printf("E. Exit the program ");

RanOnce = 1;

}