关于解绑 cin cout

#include <bits/stdc++.h>
using namespace std;
int n,m,k,ans=0;
string s;
char New,Old,qian,hou;//new old
int main(){
	freopen("paint.in","r",stdin);
	freopen("paint.out","w",stdout);
	ios::sync_with_stdio(false);
	cout.tie(0);
	cin >> n >> m >> s;
	for(int i=0;i<s.size();i++){
		if(s[i]!=s[i-1])ans++;
	}
//	cout<<ans<<endl;
//	for(int i=0;i<n;i++)cout<<a[i]<<" ";
	for(int i=1;i<=m;i++){
		cin >> k >> New;k--;
		Old=s[k];
		qian=s[k-1],hou=s[k+1];
		s[k]=New;
		if(New!=qian && New!=hou && Old==qian && Old==hou)ans+=2;//
		else if(Old!=qian && Old!=hou && New==qian && New==hou)ans-=2;//
		else if(New!=qian && New!=hou && (Old==qian || Old==hou))ans++;//
		else if(Old!=qian && Old!=hou && (New==qian || New==hou))ans--;//
		cout<<ans<<"\n";
	}
	fclose(stdin);
	fclose(stdout);
	return 0;
}//1AAA1 1AAC
/*ACB AAB ABB 1-3
2 A
3 C
4 C
3 A
4 A
6 Z
ABBBAA 3
AABBAA 3 A与前面的一样，与后面的不一样 
AACBAA 4 C与前后都不一样 
AACCAA 3
AAACAA 3
AAAAAA 1
AAAAAZ
*/