v1
9/3/2020 by nikkypizza -00
Setup JavaScript
const testCases = [
{test:[1,3,2,14,6,11,5,13,12], result: '1-3, 5, 6, 11-14'},
{test:[7,8,9,1,4,0,-1,5], result: '-1-1, 4, 5, 7-9'},
{test:[1,3,2,14,6,11,5,13,12,0,15,17], result: '0-3, 5, 6, 11-15, 17'},
{test:[7,8,9,1,4,0,-1,5], result: '-1-1, 4, 5, 7-9'},
{test:[-77,-78,-79,-10,-40,0,-1,-2], result: '-79--77, -40, -10, -2-0'},
{test:[-77,-78,-79,-10,-40,0,-3,-2,-4], result: '-79--77, -40, -10, -4--2, 0'},
{test:[17, 16, 14, 13, 11, 10, 9, 0, 1, 3, 7, 8], result:'0, 1, 3, 7-11, 13, 14, 16, 17'},
{test:[1], result: '1'},
{test:[], result: ''},
{test:undefined, result: ''}
];
runTests = (cb) => {
testCases.forEach((item, index) => {
Object.freeze(item);
const result = cb(item.test);
console.assert(result===item.result, {result, errorMsg:`Test${index +1}: expected ${item.result}`});
});
}ready
function getIntervals(arr) {
if (!arr || !arr.length) return '';
if (arr.length === 1) return `${arr[0]}`;
const sortedNumbers = [...arr].sort((a,b) => a - b);
let result = `${sortedNumbers[0]}`;
let sequence = 0;
const getDelimiter = (seq) => (seq === 1)? ', ': '-';
for (let i = 1; i < sortedNumbers.length; i++) {
const [prevoius,current,next] = [sortedNumbers[i-1], sortedNumbers[i], sortedNumbers[i+1]];
if ((current - prevoius === 1)) {
++sequence;
if (next === void 0) return `${result}${getDelimiter(sequence)}${current}`
continue;
}
result += `${sequence ? `${getDelimiter(sequence)}${prevoius}`: ``}, ${current}`;
sequence = 0;
}
return result;
}
runTests(getIntervals);ready
const getIntervals = (arr) => {
if(!Array.isArray(arr)) return '';
const result = [];
let temp = [];
arr.sort((a, b) => a - b);
for (let i = 0; i < arr.length; i++) {
temp.push(arr[i]);
if (arr[i] + 1 !== arr[i + 1]) {
temp.length > 2 ?
result.push(`${temp[0]}-${temp[temp.length - 1]}`) :
result.push(...temp);
temp = [];
}
}
return result.join(', ');
}
runTests(getIntervals);
ready
const getIntervals = (list) => {
if (!list || !list.length ) {
return '';
}
let count = 0;
const sortedList = list.sort((a, b) => a - b);
const template = sortedList.map((item, index) => {
if (sortedList[index + 1] === item + 1) {
count++;
} else {
count = 0
}
return {value: item, count};
});
return template.reduce((acc, item, index) => {
const stringEnd = index === template.length - 1 ? '' : ', ';
if (item.count === 0) {
if (!template[index - 1] || template[index - 1].count === 0) {
acc += `${item.value}${stringEnd}`;
} else if (template[index - 1].count === 1) {
acc += `${template[index - 1].value}, ${item.value}${stringEnd}`;
} else {
acc += `${item.value - template[index - 1].count}-${item.value}${stringEnd}`;
}
}
return acc;
}, ``);
}
runTests(getIntervals);