added double jump and sitting state

term1/seminar03_initialization/05_string_sum/main.cpp

@@ -0,0 +1,35 @@
+#include <iostream>
+#include <cstdio>
+#include <string>
+
+using namespace std;
+
+int string_sum(const string& str) {
+    int res = 0;
+    int x;
+    int n = str.size();
+    int i = 0;
+    while (i < n) {
+       switch (str[i]) {
+            case '[':
+            case ',' : 
+                    sscanf((str.c_str()) + i + 1, "%d", &x);
+                    res += x;
+                    break;
+            case ']' :
+                    return res;
+            case ' ':
+                    break;
+            default:
+                    break;
+       } 
+       ++i;
+    }
+    return -1;
+}
+
+int main() {
+    string meow;
+    getline(cin, meow);
+    cout << string_sum(meow) << endl;
+}