Marked_+g+fMarked_g0sMarked_f1yxf(0)1f(s(x))g(x,s(x))g(0,y)yg(s(x),y)g(x,+(y,s(x)))+(x,0)x+(x,s(y))s(+(x,y))g(s(x),y)g(x,s(+(y,x)))f(0)1f(s(x))g(x,s(x))g(0,y)yg(s(x),y)g(x,+(y,s(x)))+(x,0)x+(x,s(y))s(+(x,y))g(s(x),y)g(x,s(+(y,x)))Marked_f(s(x))Marked_g(x,s(x))Marked_g(s(x),y)Marked_g(x,+(y,s(x)))Marked_g(s(x),y)Marked_+(y,s(x))Marked_+(x,s(y))Marked_+(x,y)Marked_g(s(x),y)Marked_g(x,s(+(y,x)))Marked_g(s(x),y)Marked_+(y,x)f(0)1f(s(x))g(x,s(x))g(0,y)yg(s(x),y)g(x,+(y,s(x)))+(x,0)x+(x,s(y))s(+(x,y))g(s(x),y)g(x,s(+(y,x)))Marked_g(s(x),y)Marked_g(x,+(y,s(x)))Marked_g(s(x),y)Marked_g(x,s(+(y,x)))Marked_g1Marked_g(s(x),y)Marked_g(x,s(+(y,x)))Marked_g(s(x),y)Marked_g(x,+(y,s(x)))f(0)1f(s(x))g(x,s(x))g(0,y)yg(s(x),y)g(x,+(y,s(x)))+(x,0)x+(x,s(y))s(+(x,y))g(s(x),y)g(x,s(+(y,x)))f(0)1f(s(x))g(x,s(x))g(0,y)yg(s(x),y)g(x,+(y,s(x)))+(x,0)x+(x,s(y))s(+(x,y))g(s(x),y)g(x,s(+(y,x)))Marked_+(x,s(y))Marked_+(x,y)Marked_+2Marked_+(x,s(y))Marked_+(x,y)f(0)1f(s(x))g(x,s(x))g(0,y)yg(s(x),y)g(x,+(y,s(x)))+(x,0)x+(x,s(y))s(+(x,y))g(s(x),y)g(x,s(+(y,x)))