#include <stdio.h>
//a{n} = -6a{n-1} -9a{n-2}, a{1}=1, a{2}=2(再帰あり版)
 
int c;
int rec(int n){
        c++;  
      if(n == 1){
         return 1;
    }
    else if(n == 2){
         return 2;
    }
    else{
         return -6 * rec(n-1) - 9 * rec(n-2);    
    }
}
 
int main(void) {
    static int n;
    //printf("数列a%dの値は%d\n", n, rec(n));
    printf("このときのrecの呼び出し回数は%d\n", c);
    return 0;
}

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