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two-sum.js
function twoSum(nums, target) {
const map = new Map();
for (let i = 0; i < nums.length; i++) {
const complement = target - nums[i];
if (map.has(complement)) {
return [map.get(complement), i];
}
map.set(nums[i], i);
}
return [];
}
const map = new Map();
for (let i = 0; i < nums.length; i++) {
const complement = target - nums[i];
if (map.has(complement)) {
return [map.get(complement), i];
}
map.set(nums[i], i);
}
return [];
}
150+Problems
3Difficulties
3Languages
1v1Battle Mode
FSRSSpaced Rep.
ArraysStringsDPTreesGraphsBinary SearchSliding WindowBacktracking
Feature / 011v1
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1v1
Battle Mode
Challenge any coder head-to-head. Same problem, same clock. First to pass all test cases wins.
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battle / live
in progress
ProblemLongest Palindromic Substring
MediumA
user 1Tests6 / 8
Elapsed08:42
B
user 2Tests4 / 8
Elapsed08:42
Time Remaining21:18
Feature / 02Spaced
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Repetition
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practice / review
3 due
Two Sum
GoodEasyReview in 4 days
Longest Increasing Subsequence
HardMediumReview in 1 day
Trapping Rain Water
EasyHardReview in 12 days
24Mastered
18Learning
12Topics