#include <stdio.h>
 
int func(int n){
       int c=0;   //計算結果を格納する変数cを定義
       if(n>10){  //もしnが10より大きければ
            c=20;   //cに20を代入
                    }
          else{   //それ以外（10以下）
                for(int i=1; i<=n ;i++){   //1からnまで繰り返す（総和）
                      c=c+i;   //cにiを代入
                     }
 
                                      }
                 return c;   //計算結果を返す
}
int main(void){
          int a,b;
         scanf("%d",&a);
             b=func(a);
               printf("%d",b);
                  return 0; 
            }
 
 

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Mg==

2