I want to match two string in the same list. I want to get words from a string and insert into list. I want to remove white space and separate by commas. Then I want to check two string in that list whether match or not.
Here is my code:
main() {
List<String> list = new List();
String str = "dog , dog , cat, tiger, lion, cat";
String strn = str.replaceAll(" " , "");
list = strn.split(",");
print(list.length);
print(list);
for (int i=0;i<list.length;i++){
if (list[i] == list[i+1]) {
print("same");
} else{
print("not same");
}
i++;
}
}
here string only check upto length 4. and white space not removed!
I also noticed that in the for loop you are incrementing i twice, the second being close to the bottom. This causes i to skip some of the indexes, so loop looks at index 0, then 2, then 4, then it stops.
I have refactored your solution slightly. I removed the second i++ and changed i < list.length to i < list.length - 1 to skip the last item as list[i + 1] will throw an out of range exception:
main() {
List<String> list = new List();
String str = "dog , dog , cat, tiger, lion, cat";
String strn = str.replaceAll(" ", "");
list = strn.split(",");
print(list.length);
print(list.join('|'));
for(int i=0; i < list.length - 1; i++){
if(list[i] == list[i+1]){
print("same");
}
else{
print("not same");
}
}
}
The result of the loop is so:
same
not same
not same
not same
not same
You can test this out on DartPad
Related
In Dart I want to take input from user 100 data into a list from console. How can I do that?
void main() {
int value;
List<int> list = [0];
var largest = list[0];
for (var i = 0; i < list.length; i++) {
list.add(stdin.readByteSync());
if (list[i] > largest) {
largest = list[i];
}
}
print(largest);
}
After some dialog in the chat we ended up with the following solution:
import 'dart:io';
void main() {
// Create empty list
final list = <int>[];
// Number of numbers we want to take
const numbersWeWant = 100;
// Loop until we got all numbers
for (var i = 0; i < numbersWeWant; i++) {
int? input;
// This loop is for asking again if we get something we don't see as a number
do {
print('Input number nr. $i:');
// Get a number. input is going to be null if the input is not a number
input = int.tryParse(stdin.readLineSync() ?? '');
} while (input == null); // loop as long as we don't got a number
// Add the number we got to the list
list.add(input);
}
// Use list.reduce to find the biggest number in the list by reducing the
// list to a single value using the compare method.
print('Largest number: ${list.reduce((a, b) => a > b ? a : b)}');
}
I have a simple exercise in Coderbyte, it just want to have a function that's WordSplit(strArr) read the array of strings stored in strArr, For example I have two elements like ["hellocat", "apple,bat,cat,goodbye,hello,yellow,why"]
I just want to to determine if the first element in the input can be split into two words, where both words exist in the dictionary that is provided in the second input.
For example: the first element can be split into two words: hello and cat because both of those words are in the dictionary.
So the program should return the two words that exist in the dictionary separated by a comma, as this result hello,cat .
I've made a recursive solution below. It checks if the string to be split starts with any word in the dictionary. If it exists, the function is called again using a substring with that first word removed.
This function only works up to the first word that isn't in the dictionary since you did not specify the expected behavior when the inputted word is not made up of words in the dictionary. You could make it throw an exception perhaps, but please specify your expectation.
void main() {
print(wordSplit(["hellocat", "apple,bat,cat,goodbye,hello,yellow,why"]));
//hello,cat
}
String wordSplit(List<String> arg) {
String wordToSplit = arg[0];
String dict = arg[1];
List<String> parsedDict = arg[1].split(',');
for(String word in parsedDict) {
if(wordToSplit.startsWith(word)) {
//If the substring would be empty, don't do more recursion
if(word.length == wordToSplit.length) {
return word;
}
return word + ',' + wordSplit([wordToSplit.substring(word.length), dict]);
}
}
return wordToSplit;
}
#include <bits/stdc++.h>
using namespace std;
vector<string> converToWords(string dict) {
vector<string> res;
string s = "";
int n = dict.length();
for(int i=0; i<n; i++) {
if(dict[i] == ',') {
res.push_back(s);
s = "";
}
else s += dict[i];
}
res.push_back(s);
s = "";
return res;
}
string solve(string str[]) {
string result = "";
string word = str[0], dict = str[1];
int n = word.length();
vector<string> vs = converToWords(dict);
unordered_set<string> ust;
for(auto it: vs) ust.insert(it);
// for(auto i=ust.begin(); i!=ust.end(); i++){
// cout<<*i<<endl;
// }
string s = "";
for(int i=0; i<n; i++) {
s += word[i];
// cout<<s<<endl;
string temp = word.substr(i+1, n-(i+1));
// cout<<temp<<endl;
if(ust.find(s) != ust.end() && ust.find(temp) != ust.end()) {
cout<<s<<endl;
cout<<temp<<endl;
result += s+","+temp;
break;
}
temp = "";
}
return result;
}
int main() {
string arr[2];
cin>>arr[0]>>arr[1];
cout << solve(arr);
return 0;
}
I want to put each word in a string into a separate string. So if my string has a list of words like, "John, Mary, Barbara" and the words are separate by a carriage return (not a comma as shown in the example), how do I put John into one string, Mary into another string and Barbara into a third string. The strings are not created so I will have to create them on the fly and that is ok. This is what I have tried:
for (n; n<100; n++){
s1 = s[n:n]
if(s1 == "\n") {
break
}
}
Since I want this separation to occur for every object (a specific column in a module) I will have to put whatever the correct code is into a loop like "for o in m do{ }.
Thank you for helping me.
Maybe these functions would help. However, you would have to get familiar with the Skip type (the DXL manual helps with that).
stringSplit() divides str into substrings based on a delimiter, returning an array (Skip type) of these substrings. If pattern is a String, then its contents are used as the delimiter when splitting str. If pattern is empty or null, the value of a single space is used. If pattern is a single space, str is split on whitespace, with leading whitespace and runs of contiguous whitespace characters ignored.
Skip stringSplit(string str, string pattern) {
if (null str) return null
if (null(pattern) || 0 == length(pattern))
pattern = " ";
Skip result = create;
int i = 0; // index for searching in str
int j = 0; // index counter for result array
bool found = true;
while (found) {
// find pattern
int pos = 0;
int len = 0;
found = findPlainText(str[i:], pattern, pos, len, true);
if (found) {
// insert into result
put(result, j++, str[i:i+pos-1]);
i += pos + len;
}
}
// append the rest after last found pattern
put(result, j, str[i:]);
return result;
}
You might prefer to remove the commas first since the last word is not followed by a comma.
stringWipe() returns a copy of str with all occurrences of characters in chars eliminated:
string stringWipe(string str, string chars) {
if (null str) return str
int lenStr = length str
if (lenStr == 0) return str
int lenChars = length(chars);
if (lenChars == 0) return str
Buffer buf = create
int i
for (i=0; i<lenStr; i++) {
char c = str[i]
bool skip = false
int j
for (j=0; j<lenChars; j++) {
if (c == chars[j]) {
skip = true
break
}
}
if (skip)
continue
buf += c
}
string result = stringOf(buf);
delete buf
return result
}
I'm trying to convert strings to arrays then compare two arrays. If the same value needs to remove from both array. Then finally merge two arrays and find array length. Below is my code
String first_name = "siva";
String second_name = "lovee";
List<String> firstnameArray=new List();
List<String> secondnameArray=new List();
firstnameArray = first_name.split('');
secondnameArray = second_name.split('');
var totalcount=0;
for (int i = 0; i < first_name.length; i++) {
for (int j = 0; j < second_name.length; j++) {
if (firstnameArray[i] == secondnameArray[j]) {
print(firstnameArray[i] + "" + " == " + secondnameArray[j]);
firstnameArray.removeAt(i);
secondnameArray.removeAt(i);
break;
}
}
}
var finalList = new List.from(firstnameArray)..addAll(secondnameArray);
print(finalList);
print(finalList.length);
But always getting this error Unsupported operation: Cannot remove from a fixed-length list can you help me how to fix this issue. Thanks.
Seems like what you are trying to do is to find the length of unique characters in given two strings. Well, the Set type is perfect for this use-case. Here's an example of what you can do:
void main() {
String first = 'abigail';
String second = 'allie';
var unique = '$first$second'.split('').toSet();
print(unique);
}
This would give you an output of:
{a, b, i, g, l, e}
On which you may perform functions like .toList(), or .where() or .length.
You can ensure that firstnameArray, secondnameArray is not a fixed-length list by initializing it as below:
var firstnameArray = new List<String>.from(first_name.split(''));
var secondnameArray= new List<String>.from(second_name.split(''));
Thereby declaring firstnameArray, secondnameArray to be a mutable copy of input.
Is there a way to split a string by some symbol but only at first occurrence?
Example: date: '2019:04:01' should be split into date and '2019:04:01'
It could also look like this date:'2019:04:01' or this date : '2019:04:01' and should still be split into date and '2019:04:01'
string.split(':');
I tried using the split() method. But it doesn't have a limit attribute or something like that.
You were never going to be able to do all of that, including trimming whitespace, with the split command. You will have to do it yourself. Here's one way:
String s = "date : '2019:04:01'";
int idx = s.indexOf(":");
List parts = [s.substring(0,idx).trim(), s.substring(idx+1).trim()];
You can split the string, skip the first item of the list created and re-join them to a string.
In your case it would be something like:
var str = "date: '2019:04:01'";
var parts = str.split(':');
var prefix = parts[0].trim(); // prefix: "date"
var date = parts.sublist(1).join(':').trim(); // date: "'2019:04:01'"
The trim methods remove any unneccessary whitespaces around the first colon.
Just use the split method on the string. It accepts a delimiter/separator/pattern to split the text by. It returns a list of values separated by the provided delimiter/separator/pattern.
Usage:
const str = 'date: 2019:04:01';
final values = string.split(': '); // Notice the whitespace after colon
Output:
Inspired by python, I've wrote this utility function to support string split with an optionally maximum number of splits. Usage:
split("a=b=c", "="); // ["a", "b", "c"]
split("a=b=c", "=", max: 1); // ["a", "b=c"]
split("",""); // [""] (edge case where separator is empty)
split("a=", "="); // ["a", ""]
split("=", "="); // ["", ""]
split("date: '2019:04:01'", ":", max: 1) // ["date", " '2019:04:01'"] (as asked in question)
Define this function in your code:
List<String> split(String string, String separator, {int max = 0}) {
var result = List<String>();
if (separator.isEmpty) {
result.add(string);
return result;
}
while (true) {
var index = string.indexOf(separator, 0);
if (index == -1 || (max > 0 && result.length >= max)) {
result.add(string);
break;
}
result.add(string.substring(0, index));
string = string.substring(index + separator.length);
}
return result;
}
Online demo: https://dartpad.dev/e9a5a8a5ff803092c76a26d6721bfaf4
I found that very simple by removing the first item and "join" the rest of the List
String date = "date:'2019:04:01'";
List<String> dateParts = date.split(":");
List<String> wantedParts = [dateParts.removeAt(0),dateParts.join(":")];
Use RegExp
string.split(RegExp(r":\s*(?=')"));
Note the use of a raw string (a string prefixed with r)
\s* matches zero or more whitespace character
(?=') matches ' without including itself
You can use extensions and use this one for separating text for the RichText/TextSpan use cases:
extension StringExtension on String {
List<String> controlledSplit(
String separator, {
int max = 1,
bool includeSeparator = false,
}) {
String string = this;
List<String> result = [];
if (separator.isEmpty) {
result.add(string);
return result;
}
while (true) {
var index = string.indexOf(separator, 0);
print(index);
if (index == -1 || (max > 0 && result.length >= max)) {
result.add(string);
break;
}
result.add(string.substring(0, index));
if (includeSeparator) {
result.add(separator);
}
string = string.substring(index + separator.length);
}
return result;
}
}
Then you can just reference this as a method for any string through that extension:
void main() {
String mainString = 'Here was john and john was here';
print(mainString.controlledSplit('john', max:1, includeSeparator:true));
}
Just convert list to string and search
productModel.tagsList.toString().contains(filterText.toLowerCase())