if(判断条件) {满足执行}
public class Main { public static void main(String[] args) { int a = 10; int b = 20; if (a == b) { System.out.println("a 和 b 相等"); } } }
if(判断条件) {满足执行} else {不满足执行}
public class Main { public static void main(String[] args) { int a = 10; int b = 20; if (a == b) { System.out.println("a 和 b 相等"); } else { System.out.println("a 和 b 不相等"); } } }
if中嵌套if
public class Main { public static void main(String[] args) { int a = 10; int b = 10; int c = 20; if (a == b) { if (b == c) { System.out.println("b 和 c 相等"); } else { System.out.println("b 和 c 不相等"); } } else { System.out.println("a 和 b 不相等"); } } }