Coding PYQ-Style Set

These are public-pattern coding questions repeatedly seen in placement prep. They are not guaranteed exact exam questions.

Set A: Easy high-frequency

Input:

5
1 2 3 4 5

Output:

Core logic:

long long sum = 0;
for (int x : a) sum += x;

Output both largest and smallest.

Core logic:

int mn = a[0], mx = a[0];
for (int x : a) {
    mn = min(mn, x);
    mx = max(mx, x);
}

Core logic:

if (x % 2 == 0) even++;
else odd++;

Reverse number and compare with original.

Use isPrime() for each number from L to R.

Handle duplicates. If all same, print no second largest or -1, depending on question.

If order matters:

unordered_set<int> seen;
vector<int> result;
for (int x : a) {
    if (!seen.count(x)) {
        seen.insert(x);
        result.push_back(x);
    }
}

If array has n-1 numbers:

expected = n * (n + 1) / 2
missing = expected - actualSum

Use long long.

Use frequency count.

Count frequency, then scan original string.

Use hash set or sorting + two pointers.

Use Kadane’s algorithm.

Normalize:

k = k % n;

For right rotation:

reverse(a.begin(), a.end());
reverse(a.begin(), a.begin() + k);
reverse(a.begin() + k, a.end());

Use two pointers.

Use array of size 256 or map.

Implement without looking:

If you can code these cleanly, you are ready for most easy/medium placement coding questions.