1005 alg

Author: ggjae

cpp/2559.cpp

@@ -0,0 +1,37 @@
+#include <iostream>
+using namespace std;
+ 
+int arr[100001];
+long long int ans;
+ 
+int main() {
+    int N, K;
+    cin >> N >> K;
+
+    for (int i = 0; i < N; i++) {
+        cin >> arr[i];
+    }
+
+    int s = 0;
+    long long int sum = 0;
+
+    for (int i = s; i < s+K; i++) {
+        sum += arr[i];
+    }
+
+    ans = sum;
+ 
+    while (true) {
+        sum -= arr[s];
+        if (s+K >= N) {
+            break;
+        }
+        sum += arr[s+K];
+        if (sum > ans) {
+            ans = sum;
+        }
+        s++;
+    }
+    cout << ans;
+    return 0;
+}

cpp/2725.cpp

@@ -0,0 +1,35 @@
+#include<iostream>
+
+using namespace std;
+
+int arr[1001];
+
+int gcd(int a, int b) {
+	int t;
+	while (b) {
+		t = a % b;
+		a = b;
+		b = t;
+	}
+	return a;
+}
+
+int main() {
+	int c;
+	cin >> c;
+	arr[1] = 3;
+	for (int i = 2; i <= 1000; i++) {
+		int cnt = 0;
+		for (int j = 1; j < i; j++) {
+			if (gcd(i, j) == 1)
+				cnt++;
+		}
+		arr[i] = arr[i - 1] + 2 * cnt;
+	}
+	while (c--) {
+		int n;
+        cin >> n;
+		printf("%d\n", arr[n]);
+	}
+	return 0;
+}

cpp/3020.cpp

@@ -2,34 +2,34 @@
 #include <algorithm>
 #include <vector>
 using namespace std;
-int from_down[500001];
-int from_up[500001];
+
+int down[500001];
+int up[500001];
 vector<int> v;
 
 int main() {
-	ios_base::sync_with_stdio(false); cin.tie(NULL); cout.tie(NULL);
 	int num, height, val;
 	cin >> num >> height;
 	for (int i = 0; i < num; i++) {
 		cin >> val;
-		if (i % 2 == 0) from_down[val]++;
-		else from_up[val]++;		
+		if (i % 2 == 0) down[val]++;
+		else up[val]++;		
 	}
 	for (int i = height-1; i >= 1; i--) {
-		from_down[i] += from_down[i + 1];		//아래에서 부터 높이 i일때 부수는 장애물의 수
-		from_up[i] += from_up[i + 1];			//위에서 부터 높이 i일때 부수는 장애물의 수
+		down[i] += down[i + 1];
+		up[i] += up[i + 1];
 	}
-	//밑에서부터 높이 i일때 부수는 장애물 수
 	for (int i = 1; i <= height; i++)
-		v.push_back(from_down[i] + from_up[height - i + 1]);
+		v.push_back(down[i] + up[height - i + 1]);
+
 	sort(v.begin(),v.end());
-	int dup = 1;
+
+	int ans = 1;
 	int result = v[0];
 	for (int i = 1; i < v.size(); i++) {
-		if (v[i] == result) dup++;	
+		if (v[i] == result) ans++;	
 		else break;
 	}
-	cout << result << " " << dup;
-	system("pause");
+	cout << result << " " << ans;
 	return 0;
 }