Solutions & Explanations

Browse 4,030+ detailed solutions with multiple approaches, code in Python, Java, C++ and more.

4,030 Solutions961 Easy2102 Medium967 Hard

Title	Difficulty	Acceptance	Topics	Solution
1951. All the Pairs With the Maximum Number of Common Followers	Medium	68.9%	Database	Read
1952. Three Divisors	Easy	64.6%	Enumeration Math+1	Read
1953. Maximum Number of Weeks for Which You Can Work	Medium	42.4%	Array Greedy	Read
1954. Minimum Garden Perimeter to Collect Enough Apples	Medium	55.5%	Binary Search Math	Read
1955. Count Number of Special Subsequences	Hard	52.8%	Array Dynamic Programming	Read
1956. Minimum Time For K Virus Variants to Spread	Hard	49.5%	Array Binary Search+3	Read
1957. Delete Characters to Make Fancy String	Easy	74.1%	String	Read
1958. Check if Move is Legal	Medium	50.0%	Array Enumeration+1	Read
1959. Minimum Total Space Wasted With K Resizing Operations	Medium	44.0%	Array Dynamic Programming	Read
1960. Maximum Product of the Length of Two Palindromic Substrings	Hard	32.1%	Hash Function Rolling Hash+1	Read
1961. Check If String Is a Prefix of Array	Easy	52.7%	Array String+1	Read
1962. Remove Stones to Minimize the Total	Medium	66.2%	Array Greedy+1	Read
1963. Minimum Number of Swaps to Make the String Balanced	Medium	78.0%	Greedy Stack+2	Read
1964. Find the Longest Valid Obstacle Course at Each Position	Hard	62.8%	Array Binary Indexed Tree+1	Read
1965. Employees With Missing Information	Easy	72.6%	Database	Read
1966. Binary Searchable Numbers in an Unsorted Array	Medium	63.3%	Array Binary Search	Read
1967. Number of Strings That Appear as Substrings in Word	Easy	86.1%	Array String	Read
1968. Array With Elements Not Equal to Average of Neighbors	Medium	50.9%	Array Greedy+1	Read
1969. Minimum Non-Zero Product of the Array Elements	Medium	37.5%	Greedy Math+1	Read
1970. Last Day Where You Can Still Cross	Hard	68.7%	Array Binary Search+4	Read
1971. Find if Path Exists in Graph	Easy	55.5%	Breadth-First Search Depth-First Search+2	Read
1972. First and Last Call On the Same Day	Hard	50.7%	Database	Read
1973. Count Nodes Equal to Sum of Descendants	Medium	77.4%	Binary Tree Depth-First Search+1	Read
1974. Minimum Time to Type Word Using Special Typewriter	Easy	78.5%	Greedy String	Read
1975. Maximum Matrix Sum	Medium	67.6%	Array Greedy+1	Read
1976. Number of Ways to Arrive at Destination	Medium	37.4%	Dynamic Programming Graph+2	Read
1977. Number of Ways to Separate Numbers	Hard	21.7%	Dynamic Programming String+1	Read
1978. Employees Whose Manager Left the Company	Easy	48.9%	Database	Read
1979. Find Greatest Common Divisor of Array	Easy	83.4%	Array Math+1	Read
1980. Find Unique Binary String	Medium	81.2%	Array Backtracking+2	Read
1981. Minimize the Difference Between Target and Chosen Elements	Medium	36.8%	Array Dynamic Programming+1	Read
1982. Find Array Given Subset Sums	Hard	49.7%	Array Divide and Conquer	Read
1983. Widest Pair of Indices With Equal Range Sum	Medium	54.0%	Array Hash Table+1	Read
1984. Minimum Difference Between Highest and Lowest of K Scores	Easy	66.2%	Array Sliding Window+1	Read
1985. Find the Kth Largest Integer in the Array	Medium	48.3%	Array Divide and Conquer+4	Read
1986. Minimum Number of Work Sessions to Finish the Tasks	Medium	35.3%	Array Backtracking+3	Read
1987. Number of Unique Good Subsequences	Hard	52.7%	Dynamic Programming String	Read
1988. Find Cutoff Score for Each School	Medium	66.8%	Database	Read
1989. Maximum Number of People That Can Be Caught in Tag	Medium	49.4%	Array Greedy	Read
1990. Count the Number of Experiments	Medium	49.1%	Database	Read
1991. Find the Middle Index in Array	Easy	70.5%	Array Prefix Sum	Read
1992. Find All Groups of Farmland	Medium	75.6%	Array Breadth-First Search+2	Read
1993. Operations on Tree	Medium	45.7%	Array Breadth-First Search+4	Read
1994. The Number of Good Subsets	Hard	37.8%	Array Bit Manipulation+3	Read
1995. Count Special Quadruplets	Easy	64.5%	Array Enumeration+1	Read
1996. The Number of Weak Characters in the Game	Medium	44.7%	Array Greedy+3	Read
1997. First Day Where You Have Been in All the Rooms	Medium	40.5%	Array Dynamic Programming	Read
1998. GCD Sort of an Array	Hard	50.7%	Array Math+3	Read
1999. Smallest Greater Multiple Made of Two Digits	Medium	47.4%	Enumeration Math	Read
2000. Reverse Prefix of Word	Easy	86.3%	Stack String+1	Read

#1951Medium

All the Pairs With the Maximum Number of Common Followers

Database

Acceptance: 68.9%

#1952Easy

Three Divisors

EnumerationMathNumber Theory

Acceptance: 64.6%

#1953Medium

Maximum Number of Weeks for Which You Can Work

ArrayGreedy

Acceptance: 42.4%

#1954Medium

Minimum Garden Perimeter to Collect Enough Apples

Binary SearchMath

Acceptance: 55.5%

#1955Hard

Count Number of Special Subsequences

ArrayDynamic Programming

Acceptance: 52.8%

#1956Hard

Minimum Time For K Virus Variants to Spread

ArrayBinary SearchEnumeration+2

Acceptance: 49.5%

#1957Easy

Delete Characters to Make Fancy String

String

Acceptance: 74.1%

#1958Medium

Check if Move is Legal

ArrayEnumerationMatrix

Acceptance: 50.0%

#1959Medium

Minimum Total Space Wasted With K Resizing Operations

ArrayDynamic Programming

Acceptance: 44.0%

#1960Hard

Maximum Product of the Length of Two Palindromic Substrings

Hash FunctionRolling HashString

Acceptance: 32.1%

#1961Easy

Check If String Is a Prefix of Array

ArrayStringTwo Pointers

Acceptance: 52.7%

#1962Medium

Remove Stones to Minimize the Total

ArrayGreedyHeap (Priority Queue)

Acceptance: 66.2%

#1963Medium

Minimum Number of Swaps to Make the String Balanced

GreedyStackString+1

Acceptance: 78.0%

#1964Hard

Find the Longest Valid Obstacle Course at Each Position

ArrayBinary Indexed TreeBinary Search

Acceptance: 62.8%

#1965Easy

Employees With Missing Information

Database

Acceptance: 72.6%

#1966Medium

Binary Searchable Numbers in an Unsorted Array

ArrayBinary Search

Acceptance: 63.3%

#1967Easy

Number of Strings That Appear as Substrings in Word

ArrayString

Acceptance: 86.1%

#1968Medium

Array With Elements Not Equal to Average of Neighbors

ArrayGreedySorting

Acceptance: 50.9%

#1969Medium

Minimum Non-Zero Product of the Array Elements

GreedyMathRecursion

Acceptance: 37.5%

#1970Hard

Last Day Where You Can Still Cross

ArrayBinary SearchBreadth-First Search+3

Acceptance: 68.7%

#1971Easy

Find if Path Exists in Graph

Breadth-First SearchDepth-First SearchGraph+1

Acceptance: 55.5%

#1972Hard

First and Last Call On the Same Day

Database

Acceptance: 50.7%

#1973Medium

Count Nodes Equal to Sum of Descendants

Binary TreeDepth-First SearchTree

Acceptance: 77.4%

#1974Easy

Minimum Time to Type Word Using Special Typewriter

GreedyString

Acceptance: 78.5%

#1975Medium

Maximum Matrix Sum

ArrayGreedyMatrix

Acceptance: 67.6%

#1976Medium

Number of Ways to Arrive at Destination

Dynamic ProgrammingGraphShortest Path+1

Acceptance: 37.4%

#1977Hard

Number of Ways to Separate Numbers

Dynamic ProgrammingStringSuffix Array

Acceptance: 21.7%

#1978Easy

Employees Whose Manager Left the Company

Database

Acceptance: 48.9%

#1979Easy

Find Greatest Common Divisor of Array

ArrayMathNumber Theory

Acceptance: 83.4%

#1980Medium

Find Unique Binary String

ArrayBacktrackingHash Table+1

Acceptance: 81.2%

#1981Medium

Minimize the Difference Between Target and Chosen Elements

ArrayDynamic ProgrammingMatrix

Acceptance: 36.8%

#1982Hard

Find Array Given Subset Sums

ArrayDivide and Conquer

Acceptance: 49.7%

#1983Medium

Widest Pair of Indices With Equal Range Sum

ArrayHash TablePrefix Sum

Acceptance: 54.0%

#1984Easy

Minimum Difference Between Highest and Lowest of K Scores

ArraySliding WindowSorting

Acceptance: 66.2%

#1985Medium

Find the Kth Largest Integer in the Array

ArrayDivide and ConquerHeap (Priority Queue)+3

Acceptance: 48.3%

#1986Medium

Minimum Number of Work Sessions to Finish the Tasks

ArrayBacktrackingBit Manipulation+2

Acceptance: 35.3%

#1987Hard

Number of Unique Good Subsequences

Dynamic ProgrammingString

Acceptance: 52.7%

#1988Medium

Find Cutoff Score for Each School

Database

Acceptance: 66.8%

#1989Medium

Maximum Number of People That Can Be Caught in Tag

ArrayGreedy

Acceptance: 49.4%

#1990Medium

Count the Number of Experiments

Database

Acceptance: 49.1%

#1991Easy

Find the Middle Index in Array

ArrayPrefix Sum

Acceptance: 70.5%

#1992Medium

Find All Groups of Farmland

ArrayBreadth-First SearchDepth-First Search+1

Acceptance: 75.6%

#1993Medium

Operations on Tree

ArrayBreadth-First SearchDepth-First Search+3

Acceptance: 45.7%

#1994Hard

The Number of Good Subsets

ArrayBit ManipulationBitmask+2

Acceptance: 37.8%

#1995Easy

Count Special Quadruplets

ArrayEnumerationHash Table

Acceptance: 64.5%

#1996Medium

The Number of Weak Characters in the Game

ArrayGreedyMonotonic Stack+2

Acceptance: 44.7%

#1997Medium

First Day Where You Have Been in All the Rooms

ArrayDynamic Programming

Acceptance: 40.5%

#1998Hard

GCD Sort of an Array

ArrayMathNumber Theory+2

Acceptance: 50.7%

#1999Medium

Smallest Greater Multiple Made of Two Digits

EnumerationMath

Acceptance: 47.4%

#2000Easy

Reverse Prefix of Word

StackStringTwo Pointers

Acceptance: 86.3%

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