delete pics to save space

1.1903.cpp

@@ -0,0 +1,74 @@
+#include<cstdio>
+#include<cmath>
+#include<algorithm>
+using namespace std;
+template<typename T> inline void read(T& t)
+{
+	t=0; int ch,f=false;
+	while(ch=getchar(),!((ch>='0'&&ch<='9')||ch=='-'));
+	if(ch=='-') f=true,ch=getchar();
+	t=ch^48;
+	while(ch=getchar(),ch>='0'&&ch<='9') t=t*10+(ch^48);
+	if(f) t=-t;
+}
+template<typename T,typename... Args> inline void read(T& t,Args&... args) { read(t); read(args...); }
+const int maxn=2e6+7;
+int n,m;
+int a[maxn],bid[maxn];
+struct Query
+{
+	int l,r,pre,id;
+}Q[maxn];
+int Qcnt=0;
+struct Change
+{
+	int pos,val;
+}C[maxn];
+int Ccnt=0;
+int cnt[maxn],ans=0,blo,res[maxn];
+inline bool cmp(const Query &a,const Query &b)
+{ return bid[a.l]!=bid[b.l]?a.l<b.l:((bid[a.l]&1)?a.r<b.r:a.r>b.r); }
+inline void Work(int ti,int i)
+{
+	if(Q[i].l<=C[ti].pos&&C[ti].pos<=Q[i].r)
+	{
+		ans-=(--cnt[a[C[ti].pos]]==0);
+		ans+=(++cnt[C[ti].val]==1);
+	}
+	swap(C[ti].val,a[C[ti].pos]);
+}
+int main()
+{
+#ifdef local
+	freopen("pro.in","r",stdin);
+#endif
+	read(n,m);
+	blo=sqrt(n);
+	for(int i=1;i<=n;i++) read(a[i]),bid[i]=(i-1)/blo+1;
+	while(m--)
+	{
+		char opt[5];
+		scanf("%s",opt);
+		if(opt[0]=='Q')
+		{
+			Qcnt++; read(Q[Qcnt].l,Q[Qcnt].r);
+			Q[Qcnt].pre=Ccnt;
+			Q[Qcnt].id=Qcnt;
+		}
+		else if(opt[0]=='R') Ccnt++,read(C[Ccnt].pos,C[Ccnt].val);
+	}
+	sort(Q+1,Q+Qcnt+1,cmp);
+	int l=1,r=0,ti=0;
+	for(int i=1;i<=Qcnt;i++)
+	{
+		while(l<Q[i].l) ans-=(--cnt[a[l++]]==0);
+		while(l>Q[i].l) ans+=(++cnt[a[--l]]==1);
+		while(r<Q[i].r) ans+=(++cnt[a[++r]]==1);
+		while(r>Q[i].r) ans-=(--cnt[a[r--]]==0);
+		while(ti<Q[i].pre) Work(++ti,i);
+		while(ti>Q[i].pre) Work(ti--,i);
+		res[Q[i].id]=ans;
+	}
+	for(int i=1;i<=Qcnt;i++) printf("%d\n",res[i]);
+	return 0;
+}