CP Starter Template

Modern competitive programming starter template with fast I/O, common aliases, and contest-ready boilerplate.

[Utilities]|

Jul 9, 2026

|explanatory_notes.md|

#template#boilerplate#fast-io#starter

$cat source_code/

cpp

#include <bits/stdc++.h>
using namespace std;

using ll = long long;
using pii = pair<int, int>;
using vi = vector<int>;
using vll = vector<ll>;

#define all(x) (x).begin(), (x).end()
#define rall(x) (x).rbegin(), (x).rend()
#define pb push_back
#define sz(x) (int)(x).size()

const ll MOD = 998244353;
const ll MOD2 = 1e9 + 7;
const int MAXN = 2e5 + 5;

void solve() {

}

int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
    int t = 1;
    // cin >> t;
    while (t--) solve();
}

28 linesutf-8

$cat explanation_notes.md

notes_viewer --renderedmarkdown (math enabled)

CP Starter Template

Paste at the top of every solution to skip boilerplate.

What's Included

Fast I/O — ios_base::sync_with_stdio(false) + cin.tie(nullptr) for ~2x faster input

Type aliases — ll for long long, pii for pair, vi/vll for vectors

Macros — all(x) / rall(x) for range iterators, pb for push_back, sz(x) for safe size cast

Constants — two common mods (

998244353

and

10^9 + 7

), MAXN for array sizing

solve() — empty function where contest logic goes

Notes

cout.tie(nullptr) is optional — only helps if mixing cout and cin heavily

MAXN is set to

2 \times 10^5 + 5

by default — adjust per problem

Some contests need int main() to call solve() in a loop for multi-test — add that as needed