Google | OA Coding Questions and Solutions | Set - 9 | 2022

Question

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Here is the link :  https://www.desiqna.in/tag/google_oa

Answer 1

Google Online Assessment (OA)  | Split Strings

Given a string s with length n, how many ways can you split it into two substrings s_1 and s_2 such that the number of unique characters in s_1 and s_2 are the same?

Parameter

• s: A string with length n.

Result

• The number of ways you can split it into two substrings that satisfy the condition.

Examples

Example 1:

Input: s = "aaa"

Output: 2

Explanation: It can be split in two ways: "a", "aa" and "aa", "a".

Example 2:

Input: s = "bac"

Output: 0

Explanation: There is no way to split this string into two substrings with equal unique elements.

Constraints

• 0 <= n <= 10^5
• Characters in this string may consist of any alphanumeric character. The characters are case sensitive. That is, same letters with different cases count as different characters.

Comments

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace std;
// using namespace chrono;
using namespace __gnu_pbds;
#define pb push_back
#define inf (1LL << 60)
#define all(x) (x).begin(), (x).end()
#define prDouble(x) cout << fixed << setprecision(10) << x
#define triplet pair<int, pair<int, int>>
#define fast_io                       \
    ios_base::sync_with_stdio(false); \
    cin.tie(NULL)
#define int long long
#define max3(a, b, c) max(max(a, b), c)
#define min3(a, b, c) min(min(a, b), c)
#define max4(a, b, c, d) max(a, max3(b, c, d))
#define min4(a, b, c, d) min(a, min3(b, c, d))
#define max5(a, b, c, d, e) max(max4(a, b, c, d), e)
#define min5(a, b, c, d, e) min(min4(a, b, c, d), e)
#define MAXN 100005
#define INF 1e18
#define mod 1000000007
#define mod2 998244353
template <typename T>
using ordered_set = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>; // find_by_order, order_of_key
const int N = 1e5 + 10;
vector<int> adj[N];
int query(int l, int r)
{
    cout << "? " << l << " " << r << endl;
    int ans;
    cin >> ans;
    return ans;
}
int32_t main()
{
    fast_io;
    int tc = 1;
    cin >> tc;
    while (tc--)
    {
        string s;
        cin >> s;
        int n = s.size();
        // no of ways to split the array !!
        map<int, int> mp;
        int st[n];
        int ed[n];
        for (int i = 0; i < n; i++)
        {
            mp[s[i]]++;
            st[i] = mp.size();
        }
        mp.clear();
        for (int i = n - 1; i >= 0; i--)
        {
            mp[s[i]]++;
            ed[i] = mp.size();
        }
        int ans = 0;
        for (int i = 0; i < n; i++)
        {
            if (st[i] == ed[i + 1])
            {
                ans++;
            }
        }
        cout << ans << endl;
    }

    return 0;
}