Lesson 7 Part 1 (Brackets) - MechyKola/Codility-lessons GitHub Wiki

A string S consisting of N characters is considered to be properly nested if any of the following conditions is true:

    S is empty;
    S has the form "(U)" or "[U]" or "{U}" where U is a properly nested string;
    S has the form "VW" where V and W are properly nested strings.

For example, the string "{[()()]}" is properly nested but "([)()]" is not.

Write a function:

class Solution { public int solution(string S); }

that, given a string S consisting of N characters, returns 1 if 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.

Assume that:

    N is an integer within the range [0..200,000];
    string S consists only of the following characters: "(", "{", "[", "]", "}" and/or ")".

Complexity:

    expected worst-case time complexity is O(N);
    expected worst-case space complexity is O(N) (not counting the storage required for input arguments).

Elements of input arrays can be modified.