A. Rational Resistance
Time Limit: 1 Sec
Memory Limit: 256 MB
题目连接
http://codeforces.com/contest/343/problem/ADescription
Mad scientist Mike is building a time machine in his spare time. To finish the work, he needs a resistor with a certain resistance value.
However, all Mike has is lots of identical resistors with unit resistance R0 = 1. Elements with other resistance can be constructed from these resistors. In this problem, we will consider the following as elements:
- one resistor;
- an element and one resistor plugged in sequence;
- an element and one resistor plugged in parallel.
With the consecutive connection the resistance of the new element equals R = Re + R0. With the parallel connection the resistance of the new element equals . In this case Re equals the resistance of the element being connected.
Mike needs to assemble an element with a resistance equal to the fraction . Determine the smallest possible number of resistors he needs to make such an element.
Input
Output
Print a single number — the answer to the problem.
Please do not use the %lld specifier to read or write 64-bit integers in С++. It is recommended to use the cin, cout streams or the %I64d specifier.
Sample Input
199 200
Sample Output
200
HINT
题意
你有无数个1欧的电阻,要求你用并联和串联构成a/b欧的电阻
问你最少需要多少个电阻
题解:
首先结构肯定是串联加并联啦
a/b,整数部分由串联构成,分数部分由并联构成就好了
这样就可以不停的递归了其实
代码:
#include<stdio.h> #include<math.h> #include<iostream> using namespace std; int main() { long long a,b; scanf("%lld%lld",&a,&b); if(a<b)swap(a,b); long long ans = 0; while(a&&b) { ans += a/b; a%=b; swap(a,b); } printf("%lld ",ans); }