my question is about,how to overwrite the repeated feild in google buffer protocol
Example
message seltMeasureParam
{
repeated integer val = 1;
}
I want to fill val with 255 up to 8000 times using for loop, then i want to fill values at some particular positions within range 4000.
Filling 255 8000 times can be filled easily, i want to know how to fill val at some particular sub-range within 4000 range.
please help in this, thanks in advance
This will depend entirely on the particular language / library that you are using. For example, if I use protobuf-net, the code-gen for repeated int32 val = 1; will generate (for that member) either (syntax="proto2"; or no syntax specified):
[global::ProtoBuf.ProtoMember(1, Name = #"val")]
public int[] Vals { get; set; }
or (syntax="proto3";)
[global::ProtoBuf.ProtoMember(1, Name = #"val", IsPacked = true)]
public int[] Vals { get; set; }
So then your code is simply:
var arr = new int[8000];
for(int i = 0; i < arr.Length; i++) arr[i] = 255;
obj.Vals = arr;
and then later: just set .Vals[someIndex] = someValue; with your other values.
How that works in other libraries and languages will vary depending on the API exposed in that framework.
I am doing an edit distance with the user input. I am storing my values in array. then the edit distance will compare the user input with my array of strings. I am doing a loop that if the edit distance is more than 2 it will display invalid else valid.
The only problem I've got is that although the program is working out fine, the output is the result of all the '28' strings that I have in my array. I would like to display only invalid or valid once.
Test is my array of strings and user is - String user - the user input.
void testingLD()
{
for (int i=0; i<test.length; i++)
{
if(getLevenshteinDistance(test[i],user) > 2)
{
println ("Invalid re-input");
}
else
{
println ("Valid");
}
}
}
You have your print line functions inside your loop so they get printed once per iteration.
Try this.
void testingLD()
{
boolean isValid = true; // assume true, check each and update
// begin loop
for (int i=0; i<test.length; i++)
{
if(getLevenshteinDistance(test[i],user) > 2)
{
isValid = false;
break; // don't need to test the rest of the loop if we already found a false
}
}
// end loop
if(isValid){
println("Valid");
}else{
println("Invalid re-input");
}
}
Similarly you could count the number of valid int validCount = 0; validCount++ and then display stats about how many were valid, the percentage etc. Or keep an array of the invalid strings and display those as the ones that fail etc!
Wrap up:
When you want to check an entire collection or array for some condition and output one answer make sure to have your output outside of the loop!
This question already has answers here:
How to test whether stringstream operator>> has parsed a bad type and skip it
(5 answers)
Closed 8 years ago.
I am a little new to C++ and would really appreciate any input or suggestions! So with our intro course projects I have been looking for a way to ensure that when the prog. is asking for int values it correctly responds! That is it states its invalid in cases of both a double as well as string being entered! So if cin >> intVariable ... intVariable will not accept cin entry of "abdf" or 20.01.
So to achieve this I wrote the following function...It works but I am looking for your thoughts on how this process can be further improved!
void getIntegerOnly(int& intVariable, string coutStatement)
{
bool isInteger; // Check if value entered by user is int form or not
string tmpValue; // Variable to store temp value enetered by user
cout << coutStatement; // Output the msg for the cin statement
do
{
cin >> tmpValue; // Ask user to input their value
try // Use try to catch any exception caused by what user enetered
{
/* Ex. if user enters 20.01 then the if statement converts the
string to a form of int anf float to compare. that is int value
will be 20 and float will be 20.01. And if values do not match
then user input is not integer else it is. Keep looping untill
user enters a proper int value. Exception is 20 = 20.00 */
if (stoi(tmpValue) != stof(tmpValue))
{
isInteger = false; // Set to false!
clear_response(); // Clear response to state invalid
}
else
{
isInteger = true; //Set to true!
clear_cin(); // Clear cin to ignore all text and space in cin!
}
}
catch (...) // If the exception is trigured!
{
isInteger = false; // Set to false!
clear_response(); // Clear response to state invalid
}
} while (!isInteger); //Request user to input untill int clause met
//Store the int value to the variable passed by reference
intVariable = stoi(tmpValue);
}
This is simply an example of getting users age and age is greater than zero when running a Win32 console based application! Thank you for the feedback :)
One way would be something like the following:
std::string str;
std::cin >> str;
bool are_digits = std::all_of(
str.begin(), str.end(),
[](char c) { return isdigit(static_cast<unsigned char>(c)); }
);
return are_digits ? std::stoi(str) : throw std::invalid_argument{"Invalid input"};
and catch the exceptions on the calling side (stoi can also throw std::out_of_range).
You can leverage the second parameter of stoi().
string tmpValue;
size_t readChars;
stoi(tmpValue, &readChars);
if(readChars == tmpValue.length())
{
// input was integer
}
EDIT: this will not work for strings containing "." (for example integers passed in scientific notation).
This is not my work, but the answer to this question is what you want. Pass the string to it as a reference. It will return true is your string is an integer.
How do I check if a C++ string is an int?
So, I'm trying to make a game that requires randomly colored pictureboxes. I've been trying to make the random color generator, but I'm running into an issue that I can't explain.
When this code runs (inside of Form1_Load event):
for(int i=0; i<6, i++)
{
DateTime moment = DateTime::Now;
Random^RNG=gcnew Random(moment.Millisecond);
color[i]=RNG->Next(16);
if(color[i]<=9)
{
colorStr[i]=color[i].ToString();
}
else if(color[i]==10)
{
colorStr[i]="A";
}
else if(color[i]==11)
{
colorStr[i]="B";
}
else if(color[i]==12)
{
colorStr[i]="C";
}
else if(color[i]==13)
{
colorStr[i]="D";
}
else if(color[i]==14)
{
colorStr[i]="E";
}
else if(color[i]==15)
{
colorStr[i]="F";
}
FullColor+=colorStr[i]; //FullColor was initialized with a value of "#";
}
this->textBox1->Text=FullColor;
this->Player->BackColor = System::Drawing::ColorTranslator::FromHTML(FullColor);
The textbox displays either all the same number (i.e. #000000), or the first number will be unique, but the other five will be equal to each other (i.e. #A22222).
Random generator should not be re-created every time. Try to do it once, before the loop:
Random^RNG=gcnew Random(moment.Millisecond);
for(int i=0; i<6, i++)
{
....
(In your case, it seems that the moment.Millisecond is the same for sequential calls. But even if it would be different, the generator is not supposed to be re-created.)
Instead of the loop, you may consider the following code:
Random^ RNG = gcnew Random(); // somewhere at the beginning
....
int color = RNG->Next(0x1000000);
String^ colorStr = color.ToString("X6");
Closed. This question is opinion-based. It is not currently accepting answers.
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My group is having some discussion and strong feelings about for loop construction.
I have favored loops like:
size_t x;
for (x = 0; x < LIMIT; ++x) {
if (something) {
break;
}
...
}
// If we found what we're looking for, process it.
if (x < LIMIT) {
...
}
But others seem to prefer a Boolean flag like:
size_t x;
bool found = false;
for (x = 0; x < LIMIT && !found; ++x) {
if (something) {
found = true;
}
else {
...
}
}
// If we found what we're looking for, process it.
if (found) {
...
}
(And, where the language allows, using "for (int x = 0; ...".)
The first style has one less variable to keep track of and a simpler loop header. Albeit at the cost of "overloading" the loop control variable and (some would complain), the use of break.
The second style has clearly defined roles for the variables but a more complex loop condition and loop body (either an else, or a continue after found is set, or a "if (!found)" in the balance of the loop).
I think that the first style wins on code complexity. I'm looking for opinions from a broader audience. Pointers to actual research on which is easier to read and maintain would be even better. "It doesn't matter, take it out of your standard" is a fine answer, too.
OTOH, this may be the wrong question. I'm beginning to think that the right rule is "if you have to break out of a for, it's really a while."
bool found = false;
x = 0;
while (!found && x < LIMIT) {
if (something) {
found = true;
...handle the thing...
}
else {
...
}
++x;
}
Does what the first two examples do but in fewer lines. It does divide the initialization, test, and increment of x across three lines, though.
I'd actually dare to suggest consideration of GOTO to break out of loops in such cases:
for (size_t x = 0; x < LIMIT && !found; ++x) {
if (something)
goto found;
else {
...
}
}
// not found
...
return;
found:
...
return;
I consider this form to be both succint and readable. It may do some good in many simple cases (say, when there is no common processing in this function, in both found/unfound cases).
And about the general frowning goto receives, I find it to be a common misinterpretation of Dijkstra's original claims: his arguments favoured structured loop clauses, as for or while, over a primitive loop-via-goto, that still had a lot of presence circa 1968. Even the almighty Knuth eventualy says -
The new morality that I propose may
perhaps be stated thus: "Certain go to
statements which arise in connection with
well-understood transformations are acceptable, provided that the program documentation explains what the transformation was."
Others here occasionaly think the same.
While I disagree that an extra else really makes the 2nd more complicated, I think it's primarily a matter of aesthetics and keeping to your standard.
Personally, I have a probably irrational dislike of breaks and continues, so I'm MUCH more likely to use the found variable.
Also, note that you CAN add the found variable to the 1st implementation and do
if(something)
{
found = true;
break;
}
if you want to avoid the variable overloading problem at the expense of the extra variable, but still want the simple loop terminator...
The former example duplicates the x < LIMIT condition, whereas the latter doesn't.
With the former, if you want to change that condition, you have to remember to do it in two places.
I would prefer a different one altogether:
for (int x = 0; x < LIMIT; ++x) {
if (something) {
// If we found what we're looking for, process it.
...
break;
}
...
}
It seems you have not any trouble you mention about one or the other... ;-)
no duplication of condition, or readability problem
no additional variable
I don't have any references to hand (-1! -1!), but I seem to recall that having multiple exit points (from a function, from a loop) has been shown to cause issues with maintainability (I used to know someone who wrote code for the UK military and it was Verboten to do so). But more importantly, as RichieHindle points out, having a duplicate condition is a Bad Thing, it cries out for introducing bugs by changing one and not the other.
If you weren't using the condition later, I wouldn't be bothered either way. Since you are, the second is the way to go.
This sort of argument has been fought out here before (probably many times) such as in this question.
There are those that will argue that purity of code is all-important and they'll complain bitterly that your first option doesn't have identical post-conditions for all cases.
What I would answer is "Twaddle!". I'm a pragmatist, not a purist. I'm as against too much spaghetti code as much as the next engineer but some of the hideous terminating conditions I've seen in for loops are far worse than using a couple of breaks within your loop.
I will always go for readability of code over "purity" simply because I have to maintain it.
This looks like a place for a while loop. For loops are Syntactic Sugar on top of a While loop anyway. The general rule is that if you have to break out of a For loop, then use a While loop instead.
package com.company;
import java.io.*;
import java.util.Scanner;
public class Main {
// "line.separator" is a system property that is a platform independent and it is one way
// of getting a newline from your environment.
private static String NEWLINE = System.getProperty("line.separator");
public static void main(String[] args) {
// write your code here
boolean itsdone = false;
String userInputFileName;
String FirstName = null;
String LastName = null;
String user_junk;
String userOutputFileName;
String outString;
int Age = -1;
int rint = 0;
int myMAX = 100;
int MyArr2[] = new int[myMAX];
int itemCount = 0;
double average = 0;
double total = 0;
boolean ageDone = false;
Scanner inScan = new Scanner(System.in);
System.out.println("Enter First Name");
FirstName = inScan.next();
System.out.println("Enter Last Name");
LastName = inScan.next();
ageDone = false;
while (!ageDone) {
System.out.println("Enter Your Age");
if (inScan.hasNextInt()) {
Age = inScan.nextInt();
System.out.println(FirstName + " " + LastName + " " + "is " + Age + " Years old");
ageDone = true;
} else {
System.out.println("Your Age Needs to Have an Integer Value... Enter an Integer Value");
user_junk = inScan.next();
ageDone = false;
}
}
try {
File outputFile = new File("firstOutFile.txt");
if (outputFile.createNewFile()){
System.out.println("firstOutFile.txt was created"); // if file was created
}
else {
System.out.println("firstOutFile.txt existed and is being overwritten."); // if file had already existed
}
// --------------------------------
// If the file creation of access permissions to write into it
// are incorrect the program throws an exception
//
if ((outputFile.isFile()|| outputFile.canWrite())){
BufferedWriter fileOut = new BufferedWriter(new FileWriter(outputFile));
fileOut.write("==================================================================");
fileOut.write(NEWLINE + NEWLINE +" You Information is..." + NEWLINE + NEWLINE);
fileOut.write(NEWLINE + FirstName + " " + LastName + " " + Age + NEWLINE);
fileOut.write("==================================================================");
fileOut.close();
}
else {
throw new IOException();
}
} // end of try
catch (IOException e) { // in case for some reason the output file could not be created
System.err.format("IOException: %s%n", e);
e.printStackTrace();
}
} // end main method
}