classify the flowers based on the …

Based on the position of the ovary flowers are categorized to 3 types they are
: Hypogynous, Epigynous, and Perigynous flowers.
Hypogynous: Flowers in which the sepals, petals, and stamens are attached below the ovary are called hypogynous, and the ovaries of such flowers are said to be superior. 
Eg: tomato, tulip, and snapdragon.
Epigynous: Flowers in which the sepals, petals, and stamens appear to be attached to the upper part of the ovary due to the fusion of the hypanthium are called epigynous, and the ovaries of such flowers are said to be inferior.  Eg: daffodil
Perigynous: Flowers types in which the hypanthium forms a cuplike or tubular structure that partly surrounds the ovary are called perigynous. In such flowers, the sepals, petals, and stamens are attached to the rim of the hypanthium, and the ovaries of such flowers are superior.
 Eg: cherry, Prunus