24 lines
244 B
C++
24 lines
244 B
C++
#include<iostream>
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using namespace std;
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int func(int n){
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if(n == 1){
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return 0;
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}
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else if(n == 2){
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return 6;
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}
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else{
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return func(n - 1) + func(n - 2)*2;
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}
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}
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int main(){
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int n;
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cin >> n;
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cout << func(n);
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return 114514;
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}
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