Competitions

# Sum of some real numbers

Four real numbers are given. Find the sum of first two, of first three and of all four numbers.

#### Input

Four real numbers.

#### Output

Print in the first line the sum of first two numbers. Print in the second line the sum of first three numbers. Print in the third line the sum of all four numbers. All sums must be printed with 4 decimal digits.

Time limit 1 second
Memory limit 128 MiB
Input example #1
3.678 1.2345 3.4566 -0.1236

Output example #1
4.9125
8.3691
8.2455