📘 Week 1：C 語言基礎語法教學

重點：變數、運算、printf、資料型態、邏輯判斷
練習：每日 4 段程式碼，可獨立編譯

Day 1：變數、運算與輸出

#include <stdio.h>

int main() {
  int a = 12;
  int b = 8;
  int sum = a + b;
  int diff = a - b;
  int prod = a * b;
  int quot = a / b;

  printf("加法: %d\n", sum);
  printf("減法: %d\n", diff);
  printf("乘法: %d\n", prod);
  printf("除法: %d\n", quot);
  return 0;
}
#include <stdio.h>

int main() {
  int x = 15;
  int y = 4;
  int remainder = x % y;

  printf("15 除以 4 的餘數是 %d\n", remainder);
  return 0;
}
#include <stdio.h>

int main() {
  int score = 90;
  int bonus = 5;
  int total = score + bonus;

  printf("原始分數: %d\n", score);
  printf("加分後: %d\n", total);
  return 0;
}
#include <stdio.h>

int main() {
  int length = 7;
  int width = 3;
  int area = length * width;

  printf("長方形面積為 %d\n", area);
  return 0;
}

Day 2：資料型態與輸入

#include <stdio.h>

int main() {
  int age;
  printf("請輸入你的年齡：");
  scanf("%d", &age);
  printf("你輸入的年齡是 %d 歲。\n", age);
  return 0;
}
#include <stdio.h>

int main() {
  float height;
  printf("請輸入身高（公分）：");
  scanf("%f", &height);
  printf("你的身高是 %.1f 公分。\n", height);
  return 0;
}
#include <stdio.h>

int main() {
  char grade;
  printf("請輸入成績等級（A~F）：");
  scanf(" %c", &grade);
  printf("你輸入的等級是 %c。\n", grade);
  return 0;
}
#include <stdio.h>

int main() {
  int x;
  float y;
  printf("請輸入整數與小數：");
  scanf("%d %f", &x, &y);
  printf("整數: %d，小數: %.2f\n", x, y);
  return 0;
}

Day 3：混合運算與格式化輸出

#include <stdio.h>

int main() {
  int apples = 3;
  float price = 12.5;
  float total = apples * price;

  printf("蘋果數量: %d\n", apples);
  printf("單價: %.2f\n", price);
  printf("總價: %.2f 元\n", total);
  return 0;
}
#include <stdio.h>

int main() {
  int a = 5;
  int b = 2;
  float result = (float)a / b;

  printf("5 除以 2 的結果是 %.2f\n", result);
  return 0;
}
#include <stdio.h>

int main() {
  int x = 10;
  x += 5;
  x *= 2;

  printf("最終結果是 %d\n", x);
  return 0;
}
#include <stdio.h>

int main() {
  float pi = 3.14159;
  int r = 3;
  float area = pi * r * r;

  printf("半徑為 %d 的圓面積是 %.2f\n", r, area);
  return 0;
}

Day 4：綜合語法閱讀

#include <stdio.h>

int main() {
  int apples, bananas;
  printf("請輸入蘋果數量：");
  scanf("%d", &apples);
  printf("請輸入香蕉數量：");
  scanf("%d", &bananas);

  int total = apples + bananas;
  printf("水果總數為：%d\n", total);
  return 0;
}
#include <stdio.h>

int main() {
  float price = 12.5;
  int quantity = 4;
  float total = price * quantity;

  printf("單價：%.2f\n", price);
  printf("數量：%d\n", quantity);
  printf("總價：%.2f\n", total);
  return 0;
}
#include <stdio.h>

int main() {
  int x = 7;
  float y = 3.0;
  float result = x / y;

  printf("整數除以浮點數的結果：%.2f\n", result);
  return 0;
}
#include <stdio.h>

int main() {
  char name[20];
  int age;

  printf("請輸入姓名：");
  scanf("%s", name);
  printf("請輸入年齡：");
  scanf("%d", &age);

  printf("你好 %s，你今年 %d 歲。\n", name, age);
  return 0;
}

Day 5：資料輸入與運算組合

#include <stdio.h>

int main() {
  int base, height;
  printf("請輸入底與高：");
  scanf("%d %d", &base, &height);

  float area = 0.5 * base * height;
  printf("三角形面積為 %.2f\n", area);
  return 0;
}
#include <stdio.h>

int main() {
  int hours;
  float rate;
  printf("請輸入工時與時薪：");
  scanf("%d %f", &hours, &rate);

  float salary = hours * rate;
  printf("本週薪資為 %.2f 元\n", salary);
  return 0;
}
#include <stdio.h>

int main() {
  int x;
  printf("請輸入一個整數：");
  scanf("%d", &x);

  int square = x * x;
  printf("%d 的平方是 %d\n", x, square);
  return 0;
}
#include <stdio.h>

int main() {
  float celsius;
  printf("請輸入攝氏溫度：");
  scanf("%f", &celsius);

  float fahrenheit = celsius * 9 / 5 + 32;
  printf("華氏溫度為 %.1f°F\n", fahrenheit);
  return 0;
}

Day 6：資料型態混合與運算優先

#include <stdio.h>

int main() {
  int a = 5;
  float b = 2.0;
  float result = a + b * 3;

  printf("運算結果為 %.2f\n", result);
  return 0;
}
#include <stdio.h>

int main() {
  int x = 10;
  int y = 3;
  float z = (float)(x + y) / 2;

  printf("平均值為 %.2f\n", z);
  return 0;
}
#include <stdio.h>

int main() {
  int a = 2, b = 3, c = 4;
  int result = a + b * c;

  printf("a + b * c = %d\n", result);
  return 0;
}
#include <stdio.h>

int main() {
  float x = 5.0;
  float y = 2.0;
  float result = (x + y) / (x - y);

  printf("運算結果為 %.2f\n", result);
  return 0;
}

Day 7：綜合語法閱讀與輸出格式

#include <stdio.h>

int main() {
  char name[20];
  int birthYear;
  printf("請輸入姓名與出生年份：");
  scanf("%s %d", name, &birthYear);

  int age = 2025 - birthYear;
  printf("%s，你今年 %d 歲。\n", name, age);
  return 0;
}
#include <stdio.h>

int main() {
  int quantity;
  float unitPrice;
  printf("請輸入數量與單價：");
  scanf("%d %f", &quantity, &unitPrice);

  float total = quantity * unitPrice;
  printf("總價為 $%.2f\n", total);
  return 0;
}
#include <stdio.h>

int main() {
  int x = 7;
  int y = 4;
  printf("x = %d, y = %d\n", x, y);
  printf("x + y = %d\n", x + y);
  printf("x * y = %d\n", x * y);
  return 0;
}
#include <stdio.h>

int main() {
  float score1, score2, score3;
  printf("請輸入三科成績：");
  scanf("%f %f %f", &score1, &score2, &score3);

  float avg = (score1 + score2 + score3) / 3;
  printf("平均成績為 %.2f 分\n", avg);
  return 0;
}