Skittles

input/code.cpp: In function 'long long int initNCR(long long int, long long int)':
input/code.cpp:69:1: warning: no return statement in function returning non-void [-Wreturn-type]
   69 | }
      | ^

#include <iostream>
#include <vector>
#include <array>
#include <string>
#include <algorithm>
#include <numeric>
#include <unordered_map>
#include <unordered_set>
#include <set>
#include <queue>
#include <climits>
#include <cmath>
#include <functional>
#include <type_traits>
#include <fstream>
#include <bitset>
#include <complex>
#include <iomanip>

#include <ext/pb_ds/assoc_container.hpp> // gcc only
template<typename T>
using ordered_set = __gnu_pbds::tree<T, __gnu_pbds::null_type, std::less<T>, __gnu_pbds::rb_tree_tag, __gnu_pbds::tree_order_statistics_node_update>;
 
#define int long long
using namespace std;
 
#define cross(x, y) (((x)*conj(y)).imag())
#define sign(v) ((0 < (v)) - ((v) < 0))


int mod = 998244353;

int p(int a, int b, int m)
{
    if (b == 0) return 1;
    else if (b % 2 == 0) { int r = p(a, b/2, m); return (r*r) % m; }
    else return (p(a, b-1, m)*a) % m; 
}
int gdc(int a, int b)
{
    if (b == 0) return a;
    return gdc(b, a%b);
}
 
vector<uint32_t> facts;
int startInverse = 1;

int initNCR(int r, int maxN)
{
    facts = vector<uint32_t>(maxN+1);
    facts[0] = 1;
    int multiple = 1;
    for (int i = 1; i <= r; i++)
    {
        multiple *= i;
        multiple %= mod;
    }
    facts.at(r) = multiple;
    for (int i = r+1; i < maxN; i++)
    {
        multiple *= i;
        multiple %= mod;
        multiple *= p(i-r, mod-2, mod);
        multiple %= mod;


        facts.at(i) = multiple;
    }
}

int fastNCR(int n, int r)
{
    int val = startInverse * facts.at(n);
    val %= mod;
    return val * p(facts.at(r), mod-2, mod);
}
int fasterNCR(int c, int r)
{
    return c * p(r, mod-2, mod);
}

int nCr(int n, int r)
{
    int res = 1;
    for (int i = 0; i < r; i++)
    {
        res *= (n-i);
        res *= p(i+1, mod-2, mod);
    }
    return res;
}



void solve()
{
    int n, a, b;
    cin >> n >> a >> b;

    //initNCR(n-1, 200010);
    
    int r = n-1;

    int multiple = 1;
    for (int i = 1; i <= r; i++)
    {
        multiple *= i;
        multiple %= mod;
    }
    int rRes = multiple;
    int nCounter = r+1;

    while (nCounter <= a+n-1)
    {
        multiple *= nCounter;
        multiple %= mod;
        multiple *= p(nCounter-r, mod-2, mod);
        multiple %= mod;
        nCounter++;
    }

    int result = 0;

    for (int i = a; i <= b; i++)
    {
        //result += fastNCR(i+n-1, n-1);
        result += fasterNCR(multiple, rRes);
        result %= mod;

        multiple *= nCounter;
        multiple %= mod;
        multiple *= p(nCounter-r, mod-2, mod);
        multiple %= mod;
        nCounter++;
    }
    cout << result;
}
 
 
signed main()
{
    ios::sync_with_stdio(0);
    cin.tie(0);
    cout.precision(15);
 
    int t = 1;
 
    //cin >> t;
 
    for (int i = 0; i < t; i++)
    {
        solve();
        //cout.flush();
    }
}

Test 1

Verdict: ACCEPTED

Test 2

Verdict: ACCEPTED

Test 3

Verdict: ACCEPTED

Test 4

Verdict: ACCEPTED

Test 5

Verdict: ACCEPTED

Test 6

Verdict: ACCEPTED

Test 7

Verdict: ACCEPTED

Test 8

Verdict: ACCEPTED

Test 9

Verdict: ACCEPTED

Test 10

Verdict: ACCEPTED

Test 11

Verdict: ACCEPTED

Test 12

Verdict: ACCEPTED

Test 13

Verdict: ACCEPTED

Test 14

Verdict: ACCEPTED

Test 15

Verdict: ACCEPTED

Test 16

Verdict: ACCEPTED

Test 17

Verdict: ACCEPTED

Test 18

Verdict: ACCEPTED

Test 19

Verdict: ACCEPTED

Test 20

Verdict: ACCEPTED

Test 21

Verdict: ACCEPTED

Test 22

Verdict: ACCEPTED

Test 23

Verdict: ACCEPTED

Test 24

Verdict: ACCEPTED

Test 25

Verdict: ACCEPTED

Test 26

Verdict: ACCEPTED

Test 27

Verdict: ACCEPTED

Test 28

Verdict: ACCEPTED

Test 29

Verdict: ACCEPTED

Test 30

Verdict: ACCEPTED

Test 31

Verdict: ACCEPTED

Test 32

Verdict: ACCEPTED

Test 33

Verdict: ACCEPTED

Test 34

Verdict: ACCEPTED

Test 35

Verdict: ACCEPTED

Test 36

Verdict: ACCEPTED

Test 37

Verdict: ACCEPTED

Test 38

Verdict: ACCEPTED

Test 39

Verdict: ACCEPTED

Test 40

Verdict: ACCEPTED

Test 41

Verdict: ACCEPTED

Test 42

Verdict: ACCEPTED

Test 43

Verdict: ACCEPTED

Test 44

Verdict: ACCEPTED

Test 45

Verdict: ACCEPTED

Test 46

Verdict: ACCEPTED

Test 47

Verdict: ACCEPTED

Test 48

Verdict: ACCEPTED

Test 49

Verdict: ACCEPTED

Test 50

Verdict: ACCEPTED

Test 51

Verdict: ACCEPTED

Test 52

Verdict: ACCEPTED

Test 53

Verdict: ACCEPTED

Test 54

Verdict: ACCEPTED

Test 55

Verdict: ACCEPTED

Test 56

Verdict: ACCEPTED

Test 57

Verdict: ACCEPTED

Test 58

Verdict: ACCEPTED

Test 59

Verdict: ACCEPTED

Test 60

Verdict: ACCEPTED

Test 61

Verdict: ACCEPTED

Test 62

Verdict: ACCEPTED

Test 63

Verdict: ACCEPTED