{ll x,y,z,n;rd(x,y,z);n=x+y+z+1;combination_mint c;c.init(2*n);mint a,f;rrep(i,n)a+=(f=f*2-((-1)**(n-i))*c.C(n,i+1))*c.H(i,x)*c.H(i,y)*c.H(i,z);wt(a);}