diff --git a/c03_data/bases.c b/c03_data/bases.c
new file mode 100644
index 0000000..6803299
--- /dev/null
+++ b/c03_data/bases.c
@@ -0,0 +1,11 @@
+#include <stdio.h>
+
+int main(void)
+{
+    int x = 100;
+
+    printf("dec = %d; octal = %o; hex = %x\n", x, x, x);
+    printf("dec = %d; octal = %#o; hex = %#x\n", x, x, x);
+
+    return 0;
+}
\ No newline at end of file
diff --git a/c03_data/platinum.c b/c03_data/platinum.c
new file mode 100644
index 0000000..3c4aa59
--- /dev/null
+++ b/c03_data/platinum.c
@@ -0,0 +1,22 @@
+/* platinum.c -- your weight in platinum */
+#include <stdio.h>
+
+int main(void)
+{
+    float weight;   /* 你的体重 */
+    float value;    /* 相等我重量的白金价值 */
+
+    printf("你有黄金值钱吗？\n");
+    printf("试试看吧。\n");
+    printf("输入你的体重（单位：千克）：");
+
+    /* 获取用户的输入 */
+    scanf("%f", &weight);
+    /* 假设白金的价格是每公斤58124美元*/
+    value = 475.544 * weight * 1000;
+    printf("把你换成黄金的话，你这体重值 ¥ %.2f。\n", value);
+    printf("如果黄金降价了……\n");
+    printf("那你就多吃点来保值吧，哈哈 ^o^\n");
+
+    return 0;
+}
\ No newline at end of file
diff --git a/c03_data/print1.c b/c03_data/print1.c
new file mode 100644
index 0000000..6041910
--- /dev/null
+++ b/c03_data/print1.c
@@ -0,0 +1,14 @@
+#include <stdio.h>
+
+int main(void)
+{
+    int ten = 10;
+    int two = 2;
+
+    printf("Doing it right: ");
+    printf("%d minus %d is %d\n", ten, 2, ten - two);
+    // printf("Doing it wrong: ");
+    // printf("%d minus %d is %d\n", ten);
+
+    return 0;
+}
\ No newline at end of file
diff --git a/c03_data/print2.c b/c03_data/print2.c
new file mode 100644
index 0000000..acdd863
--- /dev/null
+++ b/c03_data/print2.c
@@ -0,0 +1,12 @@
+/* print2.c -- 更多printf()的特性 */
+#include <stdio.h>
+
+int main(void)
+{
+    printf("un = %ld and not %ld\n", 3000000000, 3000000000);
+    printf("end = %d and %d\n", 200, 200);
+    printf("big = %ld and not %d\n", 65537, 65537);
+    printf("verybig = %ld and not %ld\n", 12345678908642, 12345678908642);
+
+    return 0;
+}
\ No newline at end of file
diff --git a/c03_data/toobig.c b/c03_data/toobig.c
new file mode 100644
index 0000000..fb7edda
--- /dev/null
+++ b/c03_data/toobig.c
@@ -0,0 +1,12 @@
+#include <stdio.h>
+
+int main(void)
+{
+    int i = 2147483647;
+    unsigned int j = 4294967295;
+
+    printf("%d %d %d\n", i, i+1, i+2);
+    printf("%u %u %u\n", j, j+1, j+2);
+
+    return 0;
+}
\ No newline at end of file