let answer = 0; function check(m, d) { //console.log(m); // console.log( d + 'の分解:' + Math.floor(d / 10) + ' , ' + d % 10); //課題1. happy day なら日付を出力するコードを書いてみよう if (m === Math.floor(d / 10) + (d % 10)) { //console.log(m + ' ' + d); answer = answer + 1; } } for (let m = 1; m <=12; m++) { if (m === 1 || m === 3 ||m === 5 || m === 7 || m === 8 || m === 10 || m === 12) { for (let d = 1; d <= 31; d++) { check(m, d); } } else if (m === 4 || m === 6 || m === 9 || m === 11) { for (let d = 1; d <= 30; d++) { check(m, d); } } else { for (let d = 1; d <= 28; d++) { check(m, d); } } } console.log(answer);