题目传送门:http://codeforces.com/problemset/problem/712/C
题解:倒着推,每次都让其中一个边达到最大就是最优解
代码如下:
#include <iostream>
#include <algorithm>
#include <cstring>
#include <stdio.h>
#include <string>
#include <cmath>
#include <queue>
#include <set>
#include <map>
#include <stack>
#include <bitset>
#include <cstdlib>
using namespace std;
#define lson l,m,rt<<1
#define rson m+1,r,rt<<1|1
#define ll long long
#define ull unsigned long long
#define mem(n,v) memset(n,v,sizeof(n))
#define MAX 100005
#define MAXN 10005
#define PI 3.1415926
#define E 2.718281828459
#define opnin freopen("text.in.txt","r",stdin)
#define opnout freopen("text.out.txt","w",stdout)
#define clsin fclose(stdin)
#define clsout fclose(stdout)
#define haha1 cout << "haha1"<< endl
#define haha2 cout << "haha2"<< endl
#define haha3 cout << "haha3"<< endl
const int INF = 0x3f3f3f3f;
const ll INFF = 0x3f3f3f3f3f3f3f3f;
const double pi = 3.141592653589793;
const double inf = 1e18;
const double eps = 1e-8;
const ll mod = 1e18;
const ull mx = 133333331;
/**************************************************************************/
int main()
{
int s,e;
cin >> s >> e;
int a[3];
a[0] = a[1] = a[2] = e;
int cnt = 0;
while(a[0] < s){
a[0] = a[1] + a[2] - 1;
if(a[0] >= s) a[0] = s;
cnt++;
sort(a,a+3);
}
cout << cnt << endl;
return 0;
}