C++(clang++ 11.0.1) 解法, 执行用时: 2ms, 内存消耗: 396K, 提交时间: 2022-10-08 20:11:25

#include<iostream>
using namespace std;
int main(){
	long long a=0,b=1,c;
	long long n;
	cin>>n;
	for(long long i=3;i<=n;i++)
	{
	c=a+b;
	a=b;
	b=c;
	}
	cout<<c; 
}

Python3 解法, 执行用时: 40ms, 内存消耗: 4548K, 提交时间: 2022-01-20 09:49:16

n=[0]*51
n[1]=1
for x in range(2,len(n)):
    n[x]=n[x-1]+n[x-2]
print(n[int(input())-1])