#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define MOD (ll)1000000007
#define pii pair<int,int>
#define pll pair<ll,ll>
#define UNIQUE(v) sort(v.begin(),v.end()),v.erase(unique(v.begin(),v.end()),v.end());
ll GCD(ll a,ll b){return b?GCD(b,a%b):a;}
ll power(ll a,ll b){ll ret=1;while(b){if(b%2)ret=ret*a%MOD;a=a*a%MOD;b/=2;}return ret;}
const int sz = 1<<17;

int main()
{
    int a,b,c,d;scanf("%d %d %d %d",&a,&b,&c,&d);
    printf("%d",b-c);
    return 0;
}
#include <bits/stdc++.h>


int main() {
    const long long int MOD = 998244353;
    long long int A, B, C;
    std::cin >> A >> B >> C;

    long long int sum_a = (A + 1) * A / 2 % MOD;
    long long int sum_b = (B + 1) * B / 2 % MOD;
    long long int sum_c = (C + 1) * C / 2 % MOD;
    std::cout << ((sum_a * sum_b) % MOD) * sum_c % MOD  << std::endl;
}
