Basic use and nested use of ternary operators

 Ternary operator rules

布尔表达式?表达式1:表达式2

 Operation process: If the value of the Boolean expression is true, return the value of expression 1, otherwise return the value of expression 2

例如：
int x = 100;
int y = 50;
int z;
如果x大于y 则是true，将x赋值给z；
如果x不大于y 则是false，将y赋值给z；
z = (x > y) ? x : y;

When encountering multiple data judgments, the goal can be achieved through the nesting of ternary operations

state == 0 ? "未用" : (state == 1 ? "在用" : "停用")