#include <bits/stdc++.h>
using namespace std;
const int mod=998244353;
int b[5],a[5];
long long res;
void dfs (int x,int k) {
    if (b[x]==0) {
        if (b[0]==0&&b[1]==0&&b[2]==0) {
            res++;
            //res%=mod;
        }
        return;
    }
    b[x]--;
    dfs((x+k+3)%3,k);
    dfs((x-k+3)%3,-k);
    b[x]++;
}
int main () {
    freopen("UNO.in","r",stdin);
    freopen("UNO.out","w",stdout);
    cin >> a[0] >> a[1] >> a[2];
    for (int i=0;i<3;i++) b[i]=a[i];
    for (int i=0;i<3;i++) {
        dfs(i,1);
        res/=4;
        res%=mod;
        //for (int j=0;j<3;j++) b[i]=a[i];
        dfs(i,-1);
        res/=4;
        res%=mod;
    }
    cout << res <<endl;
    return 0;
}