# include & ltmath.h & gt
void armstrong(int a)
{
int I；
int n = 1；
int b = a；
int s = 0；
And (b/=10) n++;
b = a；
for(I = 0； I & ltn；; i ++){
s += (int)pow(b% 10，n)；
b/= 10；
}
if(s == a){
Printf("%d is the number of daffodils! \n "，a)；
} Otherwise {
Printf("%d is not daffodil! \n "，a)；
}
}
void prime(int a)
{
int I；
If (a & lt2) {
Printf("%d is not a prime number! \n "，a)；
Return;
}
for(I = 2； I & lta；; i ++){
if(a % i == 0) {
Printf("%d is not a prime number! \n "，a)；
Return;
}
}
Printf("%d is a prime number! \n "，a)；
}
void max(int a，int b，int c)
{
If (b & gta)a = b；;
if(c & gt； a)a = c；
Printf ("Maximum value: %d\n", a);
}
Void factorial (int a)
{
int I；
int f = 1；
for(I = a； I> 1; I-)
f * = I；
The factorial of printf("% d ") is: %d\n", a, f);
}
int main(int argc，char **argv)
{
int a，b，c；
Int type;
int run = 1；
Printf ("This program can do some mathematical calculations: \ n");
printf(" * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * \ n "
* 1. Determines whether a number is a daffodil number. *\n "
"* 2. Judge whether a number is a prime number. *\n "
"* 3. Find the maximum value of three numbers. *\n "
"* 4. Find the factorial of a number. *\n "
"* 0. Exit. *\n "
“* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * \ n”)；
Do {
Printf ("Please press the menu to select (0-4):");
Scanf("%d ",& type);
Switch (type)
Case 0:
while( 1){
getchar()；
Printf ("Are you sure you want to quit? (y/n)")；
a = getchar()；
Switch (a)
Case "y":
run = 0；
Break;
Case "n":
run = 1；
Break;
Default value:
Break;
}
if((a = = ' y ')| |(a = = ' n '))break；
}
Break;
Case 1:
Printf ("Please enter a number:");
scanf("%d "，& ampa)；
Armstrong (a);
Break;
Case 2:
Printf ("Please enter a number:");
scanf("%d "，& ampa)；
Prime number (a);
Break;
Case 3:
Printf ("Please enter three numbers:");
Scanf("%d%d%d ",& i, & ampb & amp；; c)；
max(a，b，c)；
Break;
Case 4:
Printf ("Please enter a number:");
scanf("%d "，& ampa)；
Factorial (a);
Break;
Default value:
Break;
}
}while (running);
Returns 0;
}