Binary Problem

CP/Codeforces Round #457 (Div. 2)/prob1.py

@@ -0,0 +1,31 @@
+n = int(input())
+a = map(str,raw_input().split(' '))
+
+a[0] = int(a[0])
+a[1] = int(a[1])
+
+a1 = a[0]//10
+a2 = a[0]%10
+b1 = a[1]//10
+b2 = a[1]%10
+
+if(a1 == 7 or a2 == 7 or b1 == 7 or b2 == 7 ):
+    print "0"
+else:
+    count = 0
+    while(not(a1 == 7 or a2 == 7 or b1 == 7 or b2 == 7)):
+        a[1]-=n
+        count+=1
+        #print(count)
+        if(a[1]<0):
+            a[1]+=60
+            a[0]-=1
+            if(a[0]<0):
+                a[0]+=24
+        a1 = a[0]//10
+        a2 = a[0]%10
+        b1 = a[1]//10
+        b2 = a[1]%10
+        continue
+    #print(count,str(a[0])+str(a[1]))
+    print(count)

CP/Codeforces Round #457 (Div. 2)/prob2.py

@@ -0,0 +1,33 @@
+from collections import deque
+n, k = map(int, raw_input().split())
+a = [i for i in xrange(64) if n >> i & 1]
+if k < len(a):
+    print 'No'
+    quit()
+s = a[-1]
+c = 0
+while len(a) + c < k:
+    if a and s == a[-1]:
+        c += 1
+        a.pop()
+    c = c * 2
+    s -= 1
+t = len(a) + c - k
+a.reverse()
+b = 0
+if t:
+    while t:
+        c -= 2
+        t -= 1
+        b += 1
+    if not a:
+        c -= 1
+        a.append(s)
+    while c > 1:
+        c -= 2
+        b += 1
+        a.extend([a.pop() - 1] * 2)
+a = [s + 1] * b + [s] * c + a
+print 'Yes'
+for x in a:
+    print x,

CP/JanuaryCookOff2018/prob3.cpp

@@ -1,91 +1,83 @@
 #include <bits/stdc++.h>
-
 using namespace std;
-
-const int oo = 1000000000;
-
-const int N = 100005;
-
-int a[N], val[N][2], f[N][2], g[N][2];
-
-void solve() {
-    int n;
-    scanf("%d", &n);
-
-    for (int i = 1; i <= n; i++) {
-        scanf("%d", a+i);
-    }
-
-    if (n == 1) {
-        printf("0\n");
-        return;
-    }
-
-    for (int i = 1; i <= n; i++) {
-        val[i][0] = a[i];
-        val[i][1] = a[n+1-i];
-    }
-
-    int m = n/2;
-    for (int i = 1; i <= m; i++)
-    for (int k = 0; k < 2; k++)
-        f[i][k] = g[i][k] = oo;
-    f[1][0] = g[1][0] = 0;
-    f[1][1] = g[1][1] = 1;
-    for (int i = 1; i < m; i++) {
-        for (int j = 0; j < 2; j++) {
-            for (int k = 0; k < 2; k++) {
-                int c1 = val[i][j];
-                int c2 = val[i+1][k];
-                if (((i & 1) && (c1 <= c2)) || (((i & 1) == 0) && c1 >= c2)) continue;
-                int t = n+1-i;
-                c1 = val[t][j];
-                c2 = val[t-1][k];
-                if (((t & 1) && (c1 <= c2)) || (((t & 1) == 0) && c1 >= c2)) continue;
-                f[i+1][k] = min(f[i+1][k], f[i][j] + k);
-            }
-            for (int k = 0; k < 2; k++) {
-                int c1 = val[i][j];
-                int c2 = val[i+1][k];
-                if (((i & 1) && (c1 >= c2)) || (((i & 1) == 0) && c1 <= c2)) continue;
-                int t = n+1-i;
-                c1 = val[t][j];
-                c2 = val[t-1][k];
-                if (((t & 1) && (c1 >= c2)) || (((t & 1) == 0) && c1 <= c2)) continue;
-                g[i+1][k] = min(g[i+1][k], g[i][j] + k);
-            }
-        }
-    }
-
-    int ans = oo;
-
-    if (n % 2 == 0) {
-        for (int j = 0; j < 2; j++) {
-            int c1 = val[m][j];
-            int c2 = val[m+1][j];
-            if (((m&1) && (c1 > c2)) || ((m&1) == 0 && (c1 < c2)))
-                ans = min(ans, f[m][j]);
-            if (((m&1) && (c1 < c2)) || ((m&1) == 0 && (c1 > c2)))
-                ans = min(ans, g[m][j]);
-        }
-    }
-    else {
-        int c1 = a[m];
-        int c2 = a[m+2];
-        int b = a[m+1];
-        if ((((m+1)&1) && b > c1 && b > c2) || (((m+1)&1) == 0 && b < c1 && b < c2))
-            ans = min(ans, min(f[m][0], f[m][1]));
-        if ((((m+1)&1) && b < c1 && b < c2) || (((m+1)&1) == 0 && b > c1 && b > c2))
-            ans = min(ans, min(g[m][0], g[m][1]));
-    }
-
-    if (ans >= oo) ans = -1;
-    printf("%d\n", ans);
+int A[100009];
+int D1[100009];
+int D2[100009];
+bool ok(int i)
+{
+	if (i % 2 == 1)
+		return A[i] < A[i + 1];
+	else
+		return A[i] > A[i + 1];
 }
-
-int main() {
-    int ct;
-    scanf("%d", &ct);
-
-    while (ct--) solve();
+int N;
+int ans()
+{
+	int i = (N + 1) / 2;
+	int j = (N + 2) / 2;
+	int id = 0;
+	D1[id] = N + 2;
+	D2[id] = N + 2;
+	if (i == j)
+	{
+		D1[id] = 0;
+		D2[id] = 0;
+	}
+	else
+	{
+		if (ok(i))
+			D1[id] = 0;
+		swap(A[i], A[j]);
+		if (ok(i))
+			D2[id] = 1;
+		swap(A[i], A[j]);
+	}
+	while (true)
+	{
+		i--;
+		j++;
+		if (i < 1)
+			break;
+		id++;
+		D1[id] = N + 2;
+		D2[id] = N + 2;
+		{
+			if (ok(i) && ok(j - 1))
+				D1[id] = min(D1[id], D1[id - 1]);
+			swap(A[i + 1], A[j - 1]);
+			if (ok(i) && ok(j - 1))
+				D1[id] = min(D1[id], D2[id - 1]);
+			swap(A[i + 1], A[j - 1]);
+		}
+		swap(A[i], A[j]);
+		{
+			if (ok(i) && ok(j - 1))
+				D2[id] = min(D2[id], 1 + D1[id - 1]);
+			swap(A[i + 1], A[j - 1]);
+			if (ok(i) && ok(j - 1))
+				D2[id] = min(D2[id], 1 + D2[id - 1]);
+			swap(A[i + 1], A[j - 1]);
+		}
+		swap(A[i], A[j]);
+	}
+	return min(D1[id], D2[id]);
+}
+int main()
+{
+	int T;
+	cin >> T;
+	while (T--)
+	{
+		cin >> N;
+		for (int i = 1; i <= N; i++)
+			cin >> A[i];
+		int out = N + 2;
+		out = min(out, ans());
+		for (int i = 1; i <= N; i++)
+			A[i] *= -1;
+		out = min(out, ans());
+		if (out > N)
+			out = -1;
+		cout << out << '\n';
+	}
 }