diff --git a/.vscode/c.code-snippets b/.vscode/c.code-snippets
index 1f2bba1..3af9204 100644
--- a/.vscode/c.code-snippets
+++ b/.vscode/c.code-snippets
@@ -83,7 +83,12 @@
   },
   "Fake loop": {
     "prefix": "fake_loop",
-    "body": ["while (0) { // Fake loop", "}"],
+    "body": ["while (0) { /* Fake loop */", "}"],
     "description": "Fake loop"
+  },
+  "Define Boolean": {
+    "prefix": "define_boolean",
+    "body": ["#define bool int", "#define true 1", "#define false 0"],
+    "description": "Define Boolean"
   }
 }
diff --git a/0311/10.c b/0311/10.c
new file mode 100644
index 0000000..f4d41d0
--- /dev/null
+++ b/0311/10.c
@@ -0,0 +1,48 @@
+#include <stdio.h>
+#define bool int
+#define true 1
+#define false 0
+#define N 10005
+#define for_i(i, range, inner)                                                 \
+    {                                                                          \
+        int i;                                                                 \
+        for (i = 0; i < range; i++)                                            \
+            inner;                                                             \
+    }
+
+bool not_prime[N];
+void pre(int n) {
+    int prime[N], prime_length = 0;
+    int i;
+    for (i = 2; i <= n; ++i) {
+        if (!not_prime[i]) {
+            prime[prime_length++] = i;
+        }
+        for_i(j, prime_length, {
+            int pri_j = prime[j];
+            if (i * pri_j > n)
+                break;
+            not_prime[i * pri_j] = true;
+            if (i % pri_j == 0) {
+                break;
+            }
+        })
+    }
+}
+
+int main() {
+    int n;
+    scanf("%d", &n);
+    pre(n);
+    {
+        int i = 2;
+        while (true) {
+            if (!not_prime[i] && !not_prime[n - i]) {
+                printf("%d=%d+%d", n, i, n - i);
+                return 0;
+            }
+            i++;
+        }
+    }
+    return 0;
+}
\ No newline at end of file
diff --git a/0311/11.c b/0311/11.c
new file mode 100644
index 0000000..bcdb352
--- /dev/null
+++ b/0311/11.c
@@ -0,0 +1,24 @@
+#include <stdio.h>
+#define for_i(i, range, inner)                                                 \
+    {                                                                          \
+        int i;                                                                 \
+        for (i = 0; i < range; i++)                                            \
+            inner;                                                             \
+    }
+
+int main() {
+    int m, n;
+    scanf("%d %d", &m, &n);
+    m = ((m % n) * (100 % n)) % n;
+    if (m > 100) {
+        return 0;
+    }
+    if (m != 0) {
+        m = n - m;
+    }
+    while (m < 100) {
+        printf("%02d ", m);
+        m += n;
+    }
+    return 0;
+}
\ No newline at end of file
diff --git a/0311/12.c b/0311/12.c
new file mode 100644
index 0000000..4adaf6e
--- /dev/null
+++ b/0311/12.c
@@ -0,0 +1,24 @@
+#include <stdio.h>
+
+int get_denominator(int line, int column) {
+    if (column + 1 - line > column) {
+        return get_denominator(line, column + 1 - line);
+    }
+    if (column == 1) {
+        return line;
+    }
+    {
+        int up = get_denominator(line - 1, column - 1);
+        int left = get_denominator(line, column - 1);
+        return up * left / (left - up);
+    }
+}
+
+int main() { 
+    int line, column;
+    scanf("%d %d", &line, &column);
+    printf("1/%d\n", get_denominator(line, column));
+    return 0; 
+    while (0) { /* Fake loop */
+    }
+}
\ No newline at end of file
diff --git a/0311/6.c b/0311/6.c
index 1e15561..87d3ff9 100644
--- a/0311/6.c
+++ b/0311/6.c
@@ -13,6 +13,7 @@ int main() {
             min = a;
     }
     printf("%d", max - min);
+    
 
     return 0;
 }
\ No newline at end of file
diff --git a/0311/7.c b/0311/7.c
new file mode 100644
index 0000000..2a84755
--- /dev/null
+++ b/0311/7.c
@@ -0,0 +1,20 @@
+#include <stdio.h>
+#define for_i(i, range, inner)                                                 \
+    {                                                                          \
+        int i;                                                                 \
+        for (i = 0; i < range; i++)                                            \
+            inner;                                                             \
+    }
+
+int main() {
+    int n, cnt=0;
+    scanf("%d", &n);
+    for_i(i, n, {
+        int a;
+        scanf("%d", &a);
+        if (a % 2 == 0)
+            cnt++;
+    })
+    printf("%d", cnt);
+    return 0;
+}
\ No newline at end of file
diff --git a/0311/8.c b/0311/8.c
new file mode 100644
index 0000000..194d79e
--- /dev/null
+++ b/0311/8.c
@@ -0,0 +1,16 @@
+#include <stdio.h>
+#define for_i(i, range, inner)                                                 \
+    {                                                                          \
+        int i;                                                                 \
+        for (i = 0; i < range; i++)                                            \
+            inner;                                                             \
+    }
+
+int main() {
+    int n, m;
+    scanf("%d %d", &n, &m);
+    for_i(i, n, {
+        for_i(j, i + 1, { printf("%d", m); });
+        printf("\n");
+    }) return 0;
+}
\ No newline at end of file
diff --git a/0311/9.c b/0311/9.c
new file mode 100644
index 0000000..08a3366
--- /dev/null
+++ b/0311/9.c
@@ -0,0 +1,23 @@
+#include <stdio.h>
+#define for_i(i, range, inner)                                                 \
+    {                                                                          \
+        int i;                                                                 \
+        for (i = 0; i < range; i++)                                            \
+            inner;                                                             \
+    }
+
+int main() {
+    int n, cnt;
+    scanf("%d", &n);
+    for_i(i, n + 1, {
+        int a = i;
+        while (a != 0) {
+            if (a % 10 == 2) {
+                cnt++;
+            }
+            a /= 10;
+        }
+    });
+    printf("%d", cnt);
+    return 0;
+}
\ No newline at end of file
diff --git a/0318/0.c b/0318-t/1.c
similarity index 100%
rename from 0318/0.c
rename to 0318-t/1.c