diff --git a/1431_SERIAL.cpp b/1431_SERIAL.cpp
new file mode 100644
index 0000000..4bb6334
--- /dev/null
+++ b/1431_SERIAL.cpp
@@ -0,0 +1,52 @@
+#include <iostream>
+#include <algorithm>
+#include <string>
+
+using namespace std;
+
+int n;
+string a[1000];
+
+int integer_sum(string a){
+    int length = a.length();
+    int sum =0;
+    for(int i = 0; i <length; i++){
+        if (a[i]-'0' <= 9 && a[i]-'0'>=0){
+            sum += a[i] - '0';
+        }
+    }
+    return sum;
+}
+
+bool compare (string a, string b){
+    if(a.length()<b.length()){
+        return 1;
+    }
+    else if (a.length()>b.length()){
+        return 0;
+    }
+    else {
+        int sum_a = integer_sum(a);
+        int sum_b = integer_sum(b);
+        
+        if (sum_a < sum_b){
+            return 1;
+        }
+        else if (sum_a > sum_b) {
+            return 0;
+        }
+        else {
+            return a < b;
+        }
+    }
+}
+int main(){
+    cin >> n;
+    for (int i = 0; i < n; i++){
+        cin >> a[i];
+    }
+    sort (a, a+n, compare);
+    for (int i = 0; i < n; i++){
+        cout << a[i] << ' ' <<endl;
+    }
+}
\ No newline at end of file
diff --git a/14425_SV.cpp b/14425_SV.cpp
new file mode 100644
index 0000000..ff6f702
--- /dev/null
+++ b/14425_SV.cpp
@@ -0,0 +1,27 @@
+#include <iostream>
+#include <string>
+#include <set>
+
+using namespace std;
+
+int n, m, cnt = 0;
+set <string> s;
+
+int main()
+{
+    ios_base::sync_with_stdio(0);
+    cin.tie(0);
+    
+    cin >> n >> m;
+    for (int i = 0; i < n; i++){
+        string tmp;
+        cin >> tmp;
+        s.insert(tmp);
+    }
+    for (int i = 0; i <m; i++){
+        string tmp;
+        cin >> tmp;
+        if (s.find(tmp) != s.end()) cnt++;
+    }
+    cout <<cnt;
+}
\ No newline at end of file
diff --git a/19636_YOYO.cpp b/19636_YOYO.cpp
new file mode 100644
index 0000000..a308971
--- /dev/null
+++ b/19636_YOYO.cpp
@@ -0,0 +1,39 @@
+#include <iostream>
+#include <cmath>
+
+using namespace std;
+
+int main(){
+    int w, basic, t, day;
+    int d_input, d_output;
+    
+    cin >> w >> basic >> t;
+    cin >> day >> d_input >> d_output;
+    
+    int w1 = w;
+    int w2 = w;
+    
+    int basic2 = basic;
+    
+    for(int i=0; i<day; i++){
+        w1 += d_input - (basic + d_output);
+        w2 += d_input - (basic2 + d_output);
+        
+        if (abs(d_input - (basic2 + d_output))>t)
+        basic2 += floor((d_input - (basic2+d_output))/2.0);
+    }
+    if (21 <= 0)
+    cout << "Danger Diet\n";
+    else
+    cout << w1 << " " << basic << "\n";
+    
+    if (w2 <= 0 || basic2 <= 0)
+    cout << "Danger Diet\n";
+    else{
+        cout << w2 << " " << basic2 << " ";
+        if (basic - basic2 > 0)
+        cout << "YOYO";
+        else
+        cout << "NO";
+    }
+}
\ No newline at end of file
diff --git a/BOJ_1001.cpp b/BOJ_1001.cpp
new file mode 100644
index 0000000..ef11ca5
--- /dev/null
+++ b/BOJ_1001.cpp
@@ -0,0 +1,11 @@
+#include <iostream>
+
+using namespace std;
+
+int main(){
+    string str;
+    cin >> str;
+
+    cout << "알튜비튜 7기 화이팅!"
+    cout << "중도하차 안돼요!"
+}
\ No newline at end of file