中缀表达式转后缀表达式和四元式详解

(1) 后缀式：abc*+ab+/ 四元式：

1. t1 = b * c
2. t2 = a + t1
3. t3 = t2 / (a + b)
4. t4 = t3 - d
5. a = t4

(2) 后缀式：xy+z≤a0∨ 四元式：

1. t1 = x + y
2. t2 = t1 <= z
3. t3 = a > 0
4. t4 = t2 or t3
5. a0 = t4

(3) 后缀式：xy+0≤ xy-2>∨ 四元式：

1. t1 = x + y
2. t2 = t1 <= 0
3. t3 = x - y
4. t4 = t3 > 2
5. t5 = t2 or t4
6. a0 = t5

(4) 后缀式：bca-a= 四元式：

1. t1 = b * c
2. t2 = t1 - a
3. t3 = t2 * a
4. a = t3