CodeArena
The premium way to practice code

Master algorithms in a workspace that feels effortless.

CodeArena is a modern competitive programming platform. Solve problems, run code against a live judge, and track your growth — all in a fast, beautiful interface.

No setup required 1200+ problems
sum-of-array-elements.cppC++
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#include <bits/stdc++.h>
using namespace std;
 
int main() {
int n; cin >> n;
long long sum = 0;
for (int i = 0; i < n; i++) {
int x; cin >> x; sum += x;
}
cout << sum;
}
Accepted · 3/3 test cases
Case 1 · 8msCase 2 · 11msCase 3 · 9ms
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A platform designed for deep work

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