URAL 1787 Turn for MEGA （贪心 + 模拟）

Turn for MEGA

Time limit: 1.0 second
Memory limit: 64 MB

A traffic light at the turn for the “MEGA” shopping center from the Novomoskovskiy highway works in such a way that  k cars are able to take a turn in one minute. At weekends all the residents of the city drive to the mall to take a shopping, which results in a huge traffic jam at the turn. Administration of the mall ordered to install a camera at the nearby bridge, which is able to calculate the number of cars approaching this turn from the city. The observation started  n minutes ago. You should use the data from the camera to determine the number of cars currently standing in the traffic jam.

Input

The first line contains integers  k and  n (1 ≤  k,  n ≤ 100), which are the number of cars that can take a turn to “MEGA” in one minute and the number of minutes passed from the beginning of observation. The second line contains space-separated integers  a 1, …,  an (0 ≤  ai ≤ 100), where  aiis the number of cars that approached the turn during the  i-th minute. The observation started at morning, when there were no cars at the turn.

Output

Output the number of cars currently standing in the traffic jam.

Samples

input	output
5 3 6 7 2	0
5 3 20 0 0	5

题意：一个路口，可以同时允许k辆车调头，已知n分钟内到达该路口的车辆，问此时还有多少车辆堵在路上不能调头。

解析：按实际的情况模拟即可。该分钟没有通过的车辆，会堵在路口等待下分钟通行，但是即使该分钟通过的车辆不足k，下一分钟还没有来的车辆也不能补上！！！

AC代码：

#include 
#include 
#include 
using namespace std;

int main(){
    #ifdef sxk
        freopen("in.txt", "r", stdin);
    #endif //sxk

    int k, n, car;
    while(cin>>k>>n){
        int ans = 0;             //当前未通过的车辆
        for(int i=0; i>car;
            if(ans + car > k) ans += car - k;   //不能完全通过 
            else ans = 0;
        }
        cout<