Tasks Details
easy
1.
Nesting
Determine whether a given string of parentheses (single type) is properly nested.
Task Score
12%
Correctness
33%
Performance
0%
A string S consisting of N characters is called properly nested if:
- S is empty;
- S has the form "(U)" where U is a properly nested string;
- S has the form "VW" where V and W are properly nested strings.
For example, string "(()(())())" is properly nested but string "())" isn't.
Write a function:
class Solution { public int solution(string S); }
that, given a string S consisting of N characters, returns 1 if string S is properly nested and 0 otherwise.
For example, given S = "(()(())())", the function should return 1 and given S = "())", the function should return 0, as explained above.
Write an efficient algorithm for the following assumptions:
- N is an integer within the range [0..1,000,000];
- string S is made only of the characters '(' and/or ')'.
Copyright 2009–2024 by Codility Limited. All Rights Reserved. Unauthorized copying, publication or disclosure prohibited.
Solution
Programming language used C#
Time spent on task 10 minutes
Notes
not defined yet
Task timeline
Code: 15:49:56 UTC,
cs,
verify,
result: Failed
using System;
// you can also use other imports, for example:
// using System.Collections.Generic;
// you can use Console.WriteLine for debugging purposes, e.g.
// Console.WriteLine("this is a debug message");
class Solution {
public int solution(string S) {
// write your code in C# 6.0 with .NET 4.5 (Mono)
long stack=0;
long size = S.Length;
for (long i = 0;i<size;i++)
{
if(S[i].ToString == "(")
stack ++;
if(S[i].ToString == ")")
stack --;
}
if (stack == 0)
return 1;
else
return 0;
}
}
Analysis
Compile error
Compilation failed: 4 error(s), 0 warnings Solution.cs(15,17): error CS1502: The best overloaded method match for `string.this[int]' has some invalid arguments /opt/codility-mono/lib/mono/4.5/mscorlib.dll (Location of the symbol related to previous error) Solution.cs(15,18): error CS1503: Argument `#1' cannot convert `long' expression to type `int' Solution.cs(17,17): error CS1502: The best overloaded method match for `string.this[int]' has some invalid arguments /opt/codility-mono/lib/mono/4.5/mscorlib.dll (Location of the symbol related to previous error) Solution.cs(17,18): error CS1503: Argument `#1' cannot convert `long' expression to type `int'
Code: 15:50:21 UTC,
cs,
verify,
result: Failed
using System;
// you can also use other imports, for example:
// using System.Collections.Generic;
// you can use Console.WriteLine for debugging purposes, e.g.
// Console.WriteLine("this is a debug message");
class Solution {
public int solution(string S) {
// write your code in C# 6.0 with .NET 4.5 (Mono)
long stack=0;
long size = S.Length;
for (long i = 0;i<size;i++)
{
if(S[i].ToString() == "(")
stack ++;
if(S[i].ToString() == ")")
stack --;
}
if (stack == 0)
return 1;
else
return 0;
}
}
Analysis
Compile error
Compilation failed: 4 error(s), 0 warnings Solution.cs(15,17): error CS1502: The best overloaded method match for `string.this[int]' has some invalid arguments /opt/codility-mono/lib/mono/4.5/mscorlib.dll (Location of the symbol related to previous error) Solution.cs(15,18): error CS1503: Argument `#1' cannot convert `long' expression to type `int' Solution.cs(17,17): error CS1502: The best overloaded method match for `string.this[int]' has some invalid arguments /opt/codility-mono/lib/mono/4.5/mscorlib.dll (Location of the symbol related to previous error) Solution.cs(17,18): error CS1503: Argument `#1' cannot convert `long' expression to type `int'
Code: 15:50:58 UTC,
cs,
verify,
result: Failed
using System;
// you can also use other imports, for example:
// using System.Collections.Generic;
// you can use Console.WriteLine for debugging purposes, e.g.
// Console.WriteLine("this is a debug message");
class Solution {
public int solution(string S) {
// write your code in C# 6.0 with .NET 4.5 (Mono)
long stack=0;
long size = S.Length;
for (long i = 0;i<size;i++)
{
if(S[i] == "(")
stack ++;
if(S[i] == ")")
stack --;
}
if (stack == 0)
return 1;
else
return 0;
}
}
Analysis
Compile error
Compilation failed: 4 error(s), 0 warnings Solution.cs(15,17): error CS1502: The best overloaded method match for `string.this[int]' has some invalid arguments /opt/codility-mono/lib/mono/4.5/mscorlib.dll (Location of the symbol related to previous error) Solution.cs(15,18): error CS1503: Argument `#1' cannot convert `long' expression to type `int' Solution.cs(17,17): error CS1502: The best overloaded method match for `string.this[int]' has some invalid arguments /opt/codility-mono/lib/mono/4.5/mscorlib.dll (Location of the symbol related to previous error) Solution.cs(17,18): error CS1503: Argument `#1' cannot convert `long' expression to type `int'
Code: 15:51:15 UTC,
cs,
verify,
result: Failed
using System;
// you can also use other imports, for example:
using System.Collections.Generic;
// you can use Console.WriteLine for debugging purposes, e.g.
// Console.WriteLine("this is a debug message");
class Solution {
public int solution(string S) {
// write your code in C# 6.0 with .NET 4.5 (Mono)
long stack=0;
long size = S.Length;
for (long i = 0;i<size;i++)
{
if(S[i] == "(")
stack ++;
if(S[i] == ")")
stack --;
}
if (stack == 0)
return 1;
else
return 0;
}
}
Analysis
Compile error
Compilation failed: 4 error(s), 0 warnings Solution.cs(15,17): error CS1502: The best overloaded method match for `string.this[int]' has some invalid arguments /opt/codility-mono/lib/mono/4.5/mscorlib.dll (Location of the symbol related to previous error) Solution.cs(15,18): error CS1503: Argument `#1' cannot convert `long' expression to type `int' Solution.cs(17,17): error CS1502: The best overloaded method match for `string.this[int]' has some invalid arguments /opt/codility-mono/lib/mono/4.5/mscorlib.dll (Location of the symbol related to previous error) Solution.cs(17,18): error CS1503: Argument `#1' cannot convert `long' expression to type `int'
Code: 15:52:48 UTC,
cs,
verify,
result: Failed
using System;
// you can also use other imports, for example:
using System.Collections.Generic;
// you can use Console.WriteLine for debugging purposes, e.g.
// Console.WriteLine("this is a debug message");
class Solution {
public int solution(string S) {
// write your code in C# 6.0 with .NET 4.5 (Mono)
long stack=0;
long size = S.Length;
for (var i = 0;i<size;i++)
{
if(S[i].ToString == "(")
stack ++;
if(S[i].ToString == ")")
stack --;
}
if (stack == 0)
return 1;
else
return 0;
}
}
Analysis
Compile error
Compilation failed: 2 error(s), 0 warnings Solution.cs(15,12): error CS0019: Operator `==' cannot be applied to operands of type `method group' and `string' Solution.cs(17,12): error CS0019: Operator `==' cannot be applied to operands of type `method group' and `string'
Code: 15:53:14 UTC,
cs,
verify,
result: Passed
using System;
// you can also use other imports, for example:
using System.Collections.Generic;
// you can use Console.WriteLine for debugging purposes, e.g.
// Console.WriteLine("this is a debug message");
class Solution {
public int solution(string S) {
// write your code in C# 6.0 with .NET 4.5 (Mono)
long stack=0;
long size = S.Length;
for (var i = 0;i<size;i++)
{
if(S[i].ToString() == "(")
stack ++;
if(S[i].ToString() == ")")
stack --;
}
if (stack == 0)
return 1;
else
return 0;
}
}
Analysis
Code: 15:53:26 UTC,
cs,
verify,
result: Passed
using System;
// you can also use other imports, for example:
using System.Collections.Generic;
// you can use Console.WriteLine for debugging purposes, e.g.
// Console.WriteLine("this is a debug message");
class Solution {
public int solution(string S) {
// write your code in C# 6.0 with .NET 4.5 (Mono)
long stack=0;
long size = S.Length;
for (var i = 0;i<size;i++)
{
if(S[i].ToString() == "(")
stack ++;
if(S[i].ToString() == ")")
stack --;
}
if (stack == 0)
return 1;
else
return 0;
}
}
Analysis
Code: 15:53:29 UTC,
cs,
final,
score:
12
using System;
// you can also use other imports, for example:
using System.Collections.Generic;
// you can use Console.WriteLine for debugging purposes, e.g.
// Console.WriteLine("this is a debug message");
class Solution {
public int solution(string S) {
// write your code in C# 6.0 with .NET 4.5 (Mono)
long stack=0;
long size = S.Length;
for (var i = 0;i<size;i++)
{
if(S[i].ToString() == "(")
stack ++;
if(S[i].ToString() == ")")
stack --;
}
if (stack == 0)
return 1;
else
return 0;
}
}Analysis summary
The following issues have been detected: wrong answers.
Analysis
expand all
Correctness tests
negative_match
invalid structure, but the number of parentheses matches
invalid structure, but the number of parentheses matches
✘
WRONG ANSWER
got 1 expected 0
got 1 expected 0
1.
0.061 s
WRONG ANSWER,
got 1 expected 0
2.
0.060 s
WRONG ANSWER,
got 1 expected 0
1.
0.061 s
OK
simple_grouped
simple grouped positive and negative test, length=22
simple grouped positive and negative test, length=22
✘
WRONG ANSWER
got 1 expected 0
got 1 expected 0
1.
0.061 s
OK
2.
0.061 s
OK
3.
0.061 s
WRONG ANSWER,
got 1 expected 0
expand all
Performance tests
large1
simple large positive test, 10K ('s followed by 10K )'s + )(
simple large positive test, 10K ('s followed by 10K )'s + )(
✘
WRONG ANSWER
got 1 expected 0
got 1 expected 0
1.
0.066 s
OK
2.
0.061 s
WRONG ANSWER,
got 1 expected 0
large2
simple large negative test, 10K+1 ('s followed by 10K )'s + )( + ()
simple large negative test, 10K+1 ('s followed by 10K )'s + )( + ()
✘
WRONG ANSWER
got 1 expected 0
got 1 expected 0
1.
0.064 s
OK
2.
0.060 s
WRONG ANSWER,
got 1 expected 0
3.
0.060 s
OK
large_full_ternary_tree
tree of the form T=(TTT) and depth 11, length=177K+
tree of the form T=(TTT) and depth 11, length=177K+
✘
WRONG ANSWER
got 1 expected 0
got 1 expected 0
1.
0.086 s
OK
2.
0.060 s
WRONG ANSWER,
got 1 expected 0
multiple_full_binary_trees
sequence of full trees of the form T=(TT), depths [1..10..1], with/without unmatched ')' at the end, length=49K+
sequence of full trees of the form T=(TT), depths [1..10..1], with/without unmatched ')' at the end, length=49K+
✘
WRONG ANSWER
got 1 expected 0
got 1 expected 0
1.
0.068 s
OK
2.
0.068 s
OK
3.
0.060 s
WRONG ANSWER,
got 1 expected 0
broad_tree_with_deep_paths
string of the form (TTT...T) of 300 T's, each T being '(((...)))' nested 200-fold, length=120K+
string of the form (TTT...T) of 300 T's, each T being '(((...)))' nested 200-fold, length=120K+
✘
WRONG ANSWER
got 1 expected 0
got 1 expected 0
1.
0.078 s
OK
2.
0.060 s
WRONG ANSWER,
got 1 expected 0