【额外练习】选择结构

【额外练习】选择结构/7-39 选择-矩形切割.c

@@ -0,0 +1,17 @@
+#include <stdio.h>
+
+int main() {
+    double a, b, m, n;
+
+    scanf("%lf%lf%lf%lf", &a, &b, &m, &n);
+
+    if (m == a && n == b) {
+        printf("3\n");
+    } else if (m == a || n == b) {
+        printf("4\n");
+    } else {
+        printf("5\n");
+    }
+
+    return 0;
+}

【额外练习】选择结构/7-40 选择-工资计算.c

@@ -0,0 +1,24 @@
+#include <stdio.h>
+
+int main() {
+    int year;
+    double time;
+
+    scanf("%d%lf", &year, &time);
+
+    if (year >= 5) {
+        if (time <= 40) {
+            printf("%.2lf\n", time * 50);
+        } else {
+            printf("%.2lf\n", 40 * 50 + (time - 40) * 50 * 1.5);
+        }
+    } else {
+        if (time <= 40) {
+            printf("%.2lf\n", time * 30);
+        } else {
+            printf("%.2lf\n", 40 * 30 + (time - 40) * 30 * 1.5);
+        }
+    }
+
+    return 0;
+}

【额外练习】选择结构/7-41 选择-完全平方数2.c

@@ -0,0 +1,22 @@
+#include <math.h>
+#include <stdio.h>
+
+int main() {
+    int n;
+
+    scanf("%d", &n);
+
+    int x = sqrt(n);
+
+    if (x * x == n) {
+        if (x % 2 == 0) {
+            printf("Even special number\n");
+        } else {
+            printf("Odd special number\n");
+        }
+    } else {
+        printf("No\n");
+    }
+
+    return 0;
+}