delete pics to save space

2.1611.cpp

@@ -0,0 +1,51 @@
+#include<cstdio>
+#include<vector>
+#include<algorithm>
+using namespace std;
+int n;
+int a[10005];
+vector<pair<int,int>> res;
+inline void reverse(int* L,int* R)   //[L,R)
+{
+	int mid=(R-L)/2;
+	for(int i=0;i<mid;i++) swap(L[i],L[mid+i]);
+}
+int main()
+{
+#ifdef local
+	freopen("pro.in","r",stdin);
+#endif
+	int T,i,j,pos;
+	scanf("%d",&T);
+	while(T-->0)
+	{
+		scanf("%d",&n);
+		for(i=1;i<=n;i++) scanf("%d",a+i);
+		res.clear();
+		for(i=1;i<n;i++)
+		{
+			for(j=1;j<=n;j++)
+				if(a[j]==i)
+				{
+					pos=j;
+					break;
+				}
+			if(pos==i) continue;
+			if(i+(pos-i)*2-1>n)
+			{
+				int len=(n-i+1)/2;
+				res.push_back(make_pair(n-len*2+1,n));
+				reverse(a+n-len*2+1,a+n+1);
+				pos-=len;
+			}
+			reverse(a+i,a+i+(pos-i)*2);
+			res.push_back(make_pair(i,i+(pos-i)*2-1));
+		}
+		printf("%d\n",res.size());
+		for(int i=0;i<res.size();i++) printf("%d %d\n",res[i].first,res[i].second);
+	}
+	return 0;
+}
+/*
+4 3 2 1
+*/