A small program that runs with an error? Rookie advice

public static int m2(int f, int k) {

This method needs a return value, you define an int type, it needs an int return value, the method itself just prints f, nothing can be returned, you can change the return value type to void, you can also add return null to the method;

Corrected **.

public class ruby {

public static void main(string args) {

m2(100, 200);

public static int m2(int f, int k) {

return null;

Or maybe so.

public class ruby {

public static void main(string args) {

m2(100, 200);

public static void m2(int f, int k) {

public static int m2(int f, int k)

Since this function does not return a value, it is modified to the following form:

public static void m2(int f, int k)

This should be when you type, overflowing the int boundary, just pay attention, enter 8888 these numbers in the range of variables and the like, it's no problem.

What's wrong, you don't need to type letters, you should be right, you can enter numbers.

No problem. The defined n is not used and a warning will appear.

The penultimate line should be changed to: string strphonename, both of these errors may be caused by the incorrect passing of this parameter, you can correct it first, and then try to recompile it again!

Let me translate it for you'strphonename'Unclear definition, in this case one is that you don't define one is that you misspelled, here you are typosing, you define m strphonename above. So you just change the wrong line to m strphonename.

I didn't see a mistake.

Are you sure it's an error and not a warning?

The last printf is changed to %d output, take a look.

Don't know what your device is when you debug?

If you convert the double type to the int type, you will lose data.

Can you post the wrong **?

You put all the definitions of variables outside the if statement, not in the process statement.

You confuse variables with judgments, put the definition of variables outside, don't write variables in the decision, it's easy to make mistakes, and the downstairs is the correct solution.

How is that possible? It's weird that it works.

If there is printf and scanf, you must write the header file include function implementation after the function call, and it must be declared before the call.

swap() is also indispensable when defined.

int *p1,*p2;Writing it on the outside indicates that a global variable is defined, so that the two pointer variables can be used throughout the program and are not limited to a single function.

What do you want to ask? Is it a bug or an algorithm?

:2:20: error: :no such file or directory

5:19: error: :no such file or directory

It clearly means that I can't find the document, and it has nothing to do with anything. Why does GCC show such a big list, doesn't it just remind you what the problem is? The latter errors are caused by these two lines.

Under linux, you can see if there is this file under usr include (deb system can use apt-file find include command to check which package provides the required file), non-linux system is not too clear, you can also press linux to try.

Teaching everyday tools like Linux Unix as an advanced subject is very problematic in China!

It looks like there is an error in the server itself, return 500 error codes, first use the browser to access the test, if there is no error, you can try to use ** to simulate the browser, plus the header.