JavaScript_定番ハンズオン7選_2025

01_helloworld.js

console.log("main.js!!");

const inputName = prompt("名前を入力してください");
console.log("こんにちは,", inputName, "さん!!");

const inputAge = prompt("年齢を入力してください");
console.log("年齢は,", inputAge, "ですね");

const numAge = parseInt(inputAge);
if(numAge < 13){
	console.log("少年です!!");
}else if(numAge < 18){
	console.log("青年です!!");
}else if(numAge < 30){
	console.log("成人です!!");
}else if(numAge < 65){
	console.log("中年です!!");
}else{
	console.log("高齢です!!");
}

const inputSum = prompt("数字をを入力してください");
console.log("1 ~", inputSum, "までの合計値を計算します");
const numSum = parseInt(inputSum);
let numTotal = 0;
for(let i=0; i<numSum; i++){
	numTotal += i + 1;
}
console.log("合計値は", numTotal, "です");

02_dice.js

console.log("main.js!!");

//==========
// サイコロ

const rdm = Math.random() * 5;
const num = Math.floor(rdm) + 1;

console.log("サイコロ: ", num);

const showDice = (num)=>{

	if(num == 1){
		console.log("+-------+");
		console.log("|       |");
		console.log("|   ●   |");
		console.log("|       |");
		console.log("+-------+");
		return;
	}

	if(num == 2){
		console.log("+-------+");
		console.log("|     ● |");
		console.log("|       |");
		console.log("| ●     |");
		console.log("+-------+");
		return;
	}

	if(num == 3){
		console.log("+-------+");
		console.log("|     ● |");
		console.log("|   ●   |");
		console.log("| ●     |");
		console.log("+-------+");
		return;
	}

	if(num == 4){
		console.log("+-------+");
		console.log("| ●   ● |");
		console.log("|       |");
		console.log("| ●   ● |");
		console.log("+-------+");
		return;
	}

	if(num == 5){
		console.log("+-------+");
		console.log("| ●   ● |");
		console.log("|   ●   |");
		console.log("| ●   ● |");
		console.log("+-------+");
		return;
	}

	if(num == 6){
		console.log("+-------+");
		console.log("| ●   ● |");
		console.log("| ●   ● |");
		console.log("| ●   ● |");
		console.log("+-------+");
		return;
	}
}

showDice(num);

03_omikuji.js

console.log("main.js!!");

//==========
// おみくじ

const rdm = Math.random() * 7;
const num = Math.floor(rdm);

if(rdm == 0){
	console.log("大吉です!!");
}else if(rdm == 1){
	console.log("中吉です!!");
}else if(rdm == 2){
	console.log("小吉です!!");
}else if(rdm == 3){
	console.log("吉です!!");
}else if(rdm == 4){
	console.log("末吉です!!");
}else if(rdm == 5){
	console.log("凶です!!");
}else{
	console.log("大凶です!!");
}

04_find_number.js

console.log("main.js!!");

//==========
// 数字当てゲーム

console.log("== 数字当てゲーム ==");

let nMin = 0;
let nMax = 10;
const rdm = Math.random() * (nMax-nMin);
const nAnswer = Math.floor(rdm) + nMin;

while(true){

	const msg = "ヒント: " + nMin + "~" + nMax + " までの範囲です";
	const input = prompt(msg);
	if(input == "q") break;

	const nInput = parseInt(input);
	if(Number.isNaN(nInput)) continue;

	if(nInput < nAnswer){
		alert("残念、" + input + "より大きい数字です");
		nMin = nInput + 1;
		continue;
	}

	if(nAnswer < nInput){
		alert("残念、" + input + "より小さい数字です");
		nMax = nInput - 1;
		continue;
	}

	alert("正解です: " + nAnswer)
	break;
}

05_pyramid.js

console.log("main.js!!");

//==========
// ピラミッド

console.log("== ピラミッド ==");

const msg = "高さを入力してください";
const input = prompt(msg);
const height = parseInt(input);

console.log("高さ: ", height);

console.log("Type-A");
for(let r=0; r<height; r++){
	let line = "";
	for(let c=0; c<r+1; c++){
		line += "*";
	}
	console.log(line);
}

console.log("Type-B");
for(let r=0; r<height; r++){
	let line = "";
	for(let c=0; c<height-(r+1); c++){
		line += "_";
	}
	for(let c=0; c<r+1; c++){
		line += "*";
	}
	console.log(line);
}

console.log("Type-C");
for(let r=0; r<height; r++){
	let line = "";
	for(let c=0; c<height-(r+1); c++){
		line += "_";
	}
	for(let c=0; c<r*2+1; c++){
		line += "*";
	}
	console.log(line);
}

06_janken.js

console.log("main.js!!");

//==========
// ジャンケン

console.log("== ジャンケン ==");

const HANDS = ["グー", "チョキ", "パー"];
const msg = "1: グー, 2: チョキ, 3, パー, q: 終了";

let nWin = 0;
let nLose = 0;
let nEven = 0;

while(true){
	const input = prompt(msg);
	if(input == "q") break;

	const nYou = parseInt(input);
	if(Number.isNaN(nYou)) continue;
	if(nYou < 1 || HANDS.length-1 < nYou) continue;

	const nCom = Math.floor(Math.random() * HANDS.length) + 1;
	const vs = "YOU: " + HANDS[nYou-1] + " vs COM: " + HANDS[nCom-1];

	const result = (nCom - nYou + 3) % 3;
	if(result == 1){
		alert(vs + " => 勝ちました");
		nWin++;
	}else if(result == 2){
		alert(vs + " => 負けました");
		nLose++;
	}else{
		alert(vs + " => あいこです");
		nEven++;
	}

	console.log("成績", "Win(", nWin, "), Lose(", nLose, "), Even(", nEven, ")");
}

07_typing_game.js

console.log("main.js!!");

//==========
// タイピングゲーム

console.log("== タイピングゲーム ==");

const WORDS = ["abc", "def", "ghi", "jkl", "mno"];
const total = WORDS.length;

let index = 0;
let score = 0;

while(true){

	const answer = WORDS[index];
	const msg = "[問" + (index+1) + "]: " + answer + ", q: 終了";

	const input = prompt(msg);
	if(input == "q") break;

	if(input == answer){
		console.log("GOOD!!");
		score++;
	}else{
		console.log("BAD...");
	}

	if(index < total-1){
		index++;
		continue;
	}

	break;
}

alert("結果:" + score + "/" + total + "点");