p3671.cpp

大概POJ上50道比较难的题的代码

#include <iostream>
using namespace std;
const int MAXN=30000;
int f[MAXN+1];
int x,n,i,j,s;
int main(){
    f[0]=0;
    cin>>n;
    for(i=1;i<=n;i++){ cin>>x; if(x==1) f[i]=f[i-1]+1; else f[i]=f[i-1];}
    s=1<<30;
    for(i=0;i<=n;i++)
        if(i-f[i]+f[n]-f[i]<s) s=i-f[i]+f[n]-f[i];
    cout<<s<<endl;
    system("pause");
}