17-miniron-v

miniron-v/DP/1699-제곱수의 합.cpp

@@ -0,0 +1,24 @@
+#include <iostream>
+#include <vector>
+
+int main() {
+	int n;
+	std::cin >> n;
+
+	std::vector<int> dp(n + 1, 0);
+	dp[1] = 1;
+
+	for (int i = 2; i <= n; ++i) {
+		int min_index = i - 1;
+
+		for (int j = 2; j * j <= i; ++j) {
+			if (dp[i - (j * j)] < dp[min_index]) {
+				min_index = i - (j * j);
+			}
+		}
+
+		dp[i] = dp[min_index] + 1;
+	}
+
+	std::cout << dp[n];
+}

miniron-v/README.md

@@ -18,4 +18,6 @@
 | 13차시 | 2024.02.06 |  DP  | [퇴사 2](https://www.acmicpc.net/problem/15486)  | [#50](https://github.com/AlgoLeadMe/AlgoLeadMe-5/pull/50) |
 | 14차시 | 2024.02.11 |  그래프, DP  | [ACM Craft](https://www.acmicpc.net/problem/1005)  | [#53](https://github.com/AlgoLeadMe/AlgoLeadMe-5/pull/53) |
 | 15차시 | 2024.02.15 |  DP, 큰 수 연산  | [타일링](https://www.acmicpc.net/problem/1793)  | [#56](https://github.com/AlgoLeadMe/AlgoLeadMe-5/pull/56) |
+| 16차시 | 2024.02.18 |  수학  | [합](https://www.acmicpc.net/problem/1081)  | [#61](https://github.com/AlgoLeadMe/AlgoLeadMe-5/pull/61) |
+| 17차시 | 2024.02.21 |  DP  | [제곱수의 합](https://www.acmicpc.net/problem/1699)  | [#64](https://github.com/AlgoLeadMe/AlgoLeadMe-5/pull/64) |
 ---

miniron-v/수학/1081-합.cpp

@@ -0,0 +1,36 @@
+#include <iostream>
+
+long long gaussSum(long long k) {
+	if (k % 2 == 0) {
+		return (k / 2) * (k + 1);
+	}
+
+	return ((k + 1) / 2) * k;
+}
+
+long long getSumOfPlace(long long n) {
+	if (n < 1) {
+		return 0;
+	}
+
+	long long answer = gaussSum(n);
+
+	long long d = 10;
+	while ((n / d) > 0) {
+		long long q = n / d;
+		long long r = n % d;
+
+		answer -= 9 * (gaussSum(q - 1) * d + q * (r + 1));
+
+		d *= 10;
+	}
+
+	return answer;
+}
+
+int main() {
+	long long l, u;
+	std::cin >> l >> u;
+
+	std::cout << getSumOfPlace(u) - getSumOfPlace(l - 1);
+}