Place rice in a saucepan. Add cold water until rice is well covered. Stir rice until water is milky and cloudy. Pour off milky water. Repeat process three times until water is clear.
Then add warm water to rice, salt and cook covered for about 10 minutes.
Gently heat the coconut milk. Dissolve sugar and salt in it while stirring. Pour the cooked rice into a glass or ceramic bowl and carefully fold in the coconut milk-sugar mixture. The rice must still be steaming hot so that the mixture is completely absorbed.
Peel the mangoes and cut into wedges or cubes.
Serve the rice and garnish with the mango pieces.