Consider the following $C$ code segment:
x = y + 1; // Line 1
y = x - 2; // Line 2
z = x + y; // Line 3
x = 5; // Line 4
y =z * 2; // Line 5
In the context of instruction-level parallelism, a dependency exists if two statements access the same memory location, and at least one access is a write.
The total number of distinct Output (Write-After-Write, WAW) data dependencies in this code segment is $\_\_\_\_$