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/**

* @param {number} num

* @return {number[]}

*/

var countBits = function (num) {

var ret = [0];

for (var i = 1; i <= num; i++) {

ret.push(countOnes(i.toString(2)));

}

return ret;

};

function countOnes(num) {

var arr = num.toString();

var ret = 0;

for (var i = 0; i < arr.length; i++) {

if (arr[i] === '1') {

ret++;

}

}

return ret;

}

/**

* @param {number} num

* @return {number[]}

*/

var countBits = function (num) {

var ret = [0];

for (var i = 1; i <= num; i++) {

// 从1开始，

// 遇到偶数时, 其1的个数和该偶数除以2得到的数字的1的个数相同，

// 遇到奇数时，其1的个数等于该奇数除以2得到的数字的1的个数再加

if (i % 2 === 0) {

ret.push(ret[parseInt(i / 2)]);

} else {

ret.push(ret[parseInt(i / 2)] + 1);

}

}

return ret;

};