I have struggling with an exercise. The client input a certain integer x, according with the integer x they will input x other y values, space-separated. The output will be the addition of each y itself, space-separated.
Example:
Input: 4 | Input: 5
21 35 55 66 | 333 53 99 12 55
Output:3 8 10 12 | Output: 9 8 18 3 10
and so on...
So far so good, my problem is that I don't understand process.stdin.on('data', function() ... )
I didn't find many videos or explanations about this.
From what I understood from 2 short videos of explanations, I did this:
let number = null;
let numOrder = [];
function clientsnum() {
process.stdout.write("Enter number: ");
process.stdin.on("data", function (data) {
number = parseInt(data.toString().trim());
process.stdin.pause();
});
process.stdin.on("pause", function () {
console.log("Paused");
process.stdout.write(`${numOrder} ${number}` + "\n"); //for debug
order();
});
}
function order() {
console.log("got here"); //for debug
process.stdout.write("numberOrder: ");
process.stdin.resume();
process.stdin.on("data", function (data) {
if (numOrder.length < number) {
numOrder.push(parseInt(data.toString().trim()));
} else {
process.exit();
}
});
process.on('exit', function() {
console.log('Over')
})
}
clientsnum();
Sometimes, I can see it doubles on the array. Also, it changes the previous statement of "number".
The exercise show us a template where I saw in other pages, by code I can understand but by practice it doesn't work when I try it "process.stdin.on('end', ...)".
If someone wants to try explain it too. I would appreciate.
Here is the template:
function main(input) {
process.stdout.write("hello " + input) //write output
}
process.stdin.resume()
process.stdin.setEncoding("utf-8")
var stdin_input = ""
process.stdin.on("data", function(input) {
stdin_input += input //read input from stdin
})
process.stdin.on("end", function (){
main(stdin_input)
})
On my second day, after a good shower thinking. I got one solution.
let numOfClient = null;
let orderID = [];
let answers = [];
let questions = ["Enter number of clients: ", "Order ID: "];
function question() {
process.stdout.write(questions[0]);
process.stdin.on("data", function (data) {
answers.push(parseInt(data.toString().trim()));
numOfClient = answers[0];
if (answers.length < numOfClient + 1) {
process.stdout.write(questions[1]); // Here the question is not answered yet
if (answers.length !== 1) { // So I need to wait for the next interation/loop
orderID.push(answers[answers.length - 1]);
}
} else {
orderID.push(answers[answers.length - 1]); // To get the last loop answer
process.exit();
}
});
process.on("exit", function () {
// for debug
console.log(
`Done, the answers [${answers}] , the numberOfClient ${numOfClient}, the orderID's [${orderID}] `
);
});
}
question();