#include <iostream>
#include <algorithm>
using namespace std;
const int mod=998244353,N=1e6+6;
typedef long long ll;
ll jc[N];
int a[3];
ll ksm(ll x,int y){
    ll res=1;
    while(y){
        if(y&1) res=res*x%mod;
        x=x*x%mod;
        y>>=1;
    }
    return res;
}
ll c(ll x,ll y){
    return jc[x]%mod*ksm((jc[y]*jc[x-y])%mod,mod-2)%mod;
}
int main(){
    freopen("UNO.in","r",stdin);
    freopen("UNO.out","w",stdout);
//    cout<<ksm(8*24,1e3);
    jc[0]=1;
    for(int i=1;i<=N-3;i++){
        jc[i]=(jc[i-1]*i)%mod;
    }
//    cout<<c(7,3);
//    cout<<jc[3]<<" "<<jc[4]<<" "<<jc[7]<<" "<<ksm(6*24,mod-2);
    for(int i=0;i<3;i++){
        cin>>a[i];
    }
    sort(a,a+3);
    cout<<c(a[0]+a[1],3);
    return 0;
}