#include
#include
#include
#include
using namespace std;
#define MAX 40
const char* taskNames[] = { "factorial", "fibonacci", "power", "productof", "sumfromzeroto", "sumof" };
enum tasks { Factorial, Fibonacci, Power, ProductOf, SumFromZeroTo, SumOf, EndOfTask };
tasks nextTask(tasks&);
tasks taskOf(char*);
void dispMainMenu();
double factorial(const int);
int fibonacci(int);
double power(int, int);
int productOf(const int, const int, const int, const int);
double sumFromZeroTo(int);
int sumof(const int, const int, const int, const int);
tasks nextTask(tasks &Task) {
switch (Task) {
case Factorial:
Task = Fibonacci;
break;
case Fibonacci:
Task = Power;
break;
case Power:
Task = ProductOf;
break;
case ProductOf:
Task = SumFromZeroTo;
break;
case SumFromZeroTo:
Task = SumOf;
break;
case SumOf:
Task = EndOfTask;
break;
case EndOfTask:
Task = EndOfTask;
break;
}
return Task;
}
tasks taskOf(char* str) {
tasks task;
for (task = Factorial; task < EndOfTask; task = nextTask(task)) {
if (strcmp(str, taskNames[task]) == 0) return task;
}
return EndOfTask;
}
int main() {
cout << "Enter command: ";
char cmdStr[MAX], cmd[MAX / 2];
gets(cmdStr);
cout << "You typed: " << cmdStr << endl;
int count, data[4];
count = sscanf(cmdStr, "%s %d %d %d %d", cmd, &data[0], &data[1], &data[2], &data[3]);
cout << count << " parts parsed: " << cmd;
for (int i = 0; i < count - 1; i++)
cout << " " << data[i];
cout << endl;
if (count < 2) //incorrect input
{
cout << "incorrect input...";
dispMainMenu("");
system("pause");
return 0;
}
// get lowercase string in taskStr
for (int i = 0; cmd[i] != '\0'; ++i) {
if (isalpha(cmd[i]))
cmd[i] = (char)(isupper(cmd[i])) ? tolower(cmd[i]) : cmd[i];
}
cout << "Normalized command: " << cmd;
for (int i = 0; i < count - 1; i++)
cout << " " << data[i];
cout << endl << endl;
switch (taskOf(cmd)) {
case Factorial: // 'factorial',
if (count < 2) cout << "Usage: Factorial ofSomeNum" << endl;
else {
cout << "task: " << taskNames[Factorial] << " of " << data[0] << endl;
cout << " " << data[0] << "! = " << factorial(data[0]) << endl << endl;
}
break;
case Fibonacci: // 'fibonacci',
if (count < 2) cout << "Usage: Fibonacci numOfItems" << endl;
else
{
cout << "task: " << taskNames[Fibonacci] << " numbers of the first " << data[0] << " terms:" << endl;
for (int i(0); i <= data[0]; i++) {
cout << "f(" << i << ")=" << fibonacci(i) << endl;
}
}
cout << endl;
break;
case Power: // 'power',
if (count < 3) cout << "Usage: Power baseNum powerNum" << endl;
else {
cout << data[0] << " to the power of " << data[1] << " = " << power(data[0], data[1]) << endl;
}
break;
case ProductOf: // 'productof',
if (count < 3) cout << "Usage: ProductOf num1 num2 [num3 [num4] ]" << endl;
else
{
cout << "task: " << taskNames[ProductOf] << endl;
int Max;
if (count > 5) Max = 5; else Max = count;
cout << " ";
for (int i = 0; i < Max - 1; i++) {
if (i < Max - 2) cout << data[i] << " * ";
else cout << data[i] << " = "; // << sum << endl;
}
switch (Max) {
case 5:
cout << productOf(data[3], data[2], data[1], data[0]) << endl;
break;
case 4:
cout << productOf(data[2], data[1], data[0]) << endl;
break;
case 3:
cout << productOf(data[1], data[0]) << endl;
break;
}
}
cout << endl;
break;
case SumFromZeroTo: // 'sumfrom0to' ,
if (count < 2) cout << "Usage: SumFromZeroTo num" << endl;
else {
cout << "task: " << taskNames[SumFromZeroTo] << " " << data[0] << endl << endl;
cout << " 0 + " << "... + (" << data[0] << ") = " << sumFromZeroTo(data[0]) << endl << endl;
}
break;
case SumOf: // 'sumof'
if (count < 3) cout << "Usage: SumOf num1 num2" << endl;
else
{
cout << "task: " << taskNames[SumOf] << endl;
int Max;
if (count > 5) Max = 5; else Max = count;
cout << " ";
for (int i = 0; i < Max - 1; i++) {
if (i < Max - 2) cout << data[i] << " + ";
else cout << data[i] << " = "; // << sum << endl;
}
switch (Max) {
case 5:
cout << sumof(data[0], data[1], data[2], data[3]) << endl;
break;
case 4:
cout << sumof(data[0], data[1], data[2]) << endl;
break;
case 3:
cout << sumof(data[0], data[1]) << endl;
break;
}
}
cout << endl;
break;
default:
cout << "No such task in the taskList..." << endl;
break;
}
system("pause");
return 0;
}
// 函数定义
void dispMainMenu() {
// TODO: 实现显示主菜单的功能
}
double factorial(const int n) {
if (n == 0) {
return 1;
} else {
return n * factorial(n - 1);
}
}
int fibonacci(int n) {
if (n <= 1) {
return n;
} else {
return fibonacci(n - 1) + fibonacci(n - 2);
}
}
double power(int x, int n) {
if (n == 0) {
return 1;
} else {
return x * power(x, n - 1);
}
}
int productOf(const int a, const int b, const int c, const int d) {
return a * b * c * d;
}
double sumFromZeroTo(int n) {
if (n == 0) {
return 0;
} else {
return n + sumFromZeroTo(n - 1);
}
}
int sumof(const int a, const int b, const int c, const int d) {
return a + b + c + d;
