Uvalive 6832 Bit String Reordering

#include <iostream>
#include <cstdio>
#include <cstring>
using namespace std;

int N,M,ans,n1,n2,m1,m2,fi,minn;
//n1 stand for the number of zero
//n2 stand for the number of one
int a[20],b[20],c[20],d[20];
bool vis[20];

void fun(){
	ans=0;
	memset(vis,false,sizeof(vis));
	for(int i=0;i<N;i++)
		d[i]=a[i];
	for(int i=0;i<N;i++){
		if(d[i]==c[i])
			continue;
		for(int j=i+1;j<N;j++){
			if(c[j]!=c[i]&&c[j]!=d[j]&&!vis[j]){
				d[i]=c[i];
				d[j]=c[j];
				ans+=(j-i);
				vis[i]=true;
				vis[j]=true;
				//test
				/*
				for(int k=0;k<N;k++)
					printf("%d ",d[k]);
				printf("\n");
				*/
				break;
			}
		}
	}
}

int main(){
	while(scanf("%d%d",&N,&M)!=EOF){
		minn=9999999;
		n1=n2=m1=m2=0;
		for(int i=0;i<N;i++){
			scanf("%d",&a[i]);
			if(a[i]==0)
				n1++;
			else
				n2++;
		}
		for(int i=0;i<M;i++){
			scanf("%d",&b[i]);
			if(i%2)
				m2+=b[i];
			else
				m1+=b[i];
		}
		//printf("%d %d %d %d\n",n1,n2,m1,m2);
		if(n1>n2){
			if(m1>m2)
				fi=0;
			else
				fi=1;
		}
		else if(n1<n2){
			if(m1<m2)
				fi=0;
			else
				fi=1;
		}
		if(n1!=n2){
			//printf("fi=%d\n",fi);
			for(int i=0,j=0;j<M;j++){
				for(int k=0;k<b[j];k++){
					c[i+k]=fi;
				}
				fi=(fi+1)%2;
				i+=b[j];
			}

			//test
			/*
			for(int i=0;i<N;i++){
				printf("%d ",c[i]);
			}	
			printf("\n");
			*/
			fun();
			minn=min(ans,minn);
		}
		else{
			fi=0;
			for(int i=0,j=0;j<M;j++){
				for(int k=0;k<b[j];k++){
					c[i+k]=fi;
				}
				fi=(fi+1)%2;
				i+=b[j];
			}
			fun();
			minn=min(ans,minn);
			fi=1;
			for(int i=0,j=0;j<M;j++){
				for(int k=0;k<b[j];k++){
					c[i+k]=fi;
				}
				fi=(fi+1)%2;
				i+=b[j];
			}
			fun();
			minn=min(ans,minn);
		}
		printf("%d\n",minn);
	}
}