每日两题day59

今天你AC了吗？

每日两题day59

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一、基础题

题目：P1421 小玉买文具 - 洛谷

思路：

涉及多种进制的题目都可以全部拆成最小的单位再处理。

代码：

#include <bits/stdc++.h>
int main() {
    int a, b, sum = 0;
    std::cin >> a >> b;
    sum = a * 10 + b;
    std::cout << (sum / 19);
    return 0;
}

二、提高题

题目：P2615 [NOIP 2015 提高组] 神奇的幻方 - 洛谷

思路：

纯模拟，按题目来的写判别函数就好了

代码：

#include <bits/stdc++.h>

int n = 40, i = 1;
std::vector<std::vector<int>> a(n, std::vector<int>(n));

std::pair<int, int> next(std::pair<int, int> b) {
    if (b.first == 0 && b.second != n - 1) {
        return {n - 1, b.second + 1};
    }
    if (b.second == n - 1 && b.first != 0) {
        return {b.first - 1, 0};
    }
    if (b.first == 0 && b.second == n - 1) {
        return {1, n - 1};
    }
    if (b.first - 1 >= 0 && b.second + 1 < n && a[b.first - 1][b.second + 1] == 0) {
        return {b.first - 1, b.second + 1};
    } else {
        return {b.first + 1, b.second};
    }
}

int main() {
    std::pair<int, int> before;
    std::cin >> n;

    a[0][n / 2] = 1;
    before = {0, n / 2};
    while (++i <= n * n) {
        before = next(before);
        a[before.first][before.second] = i;
    }
    for (int i = 0; i < n; i++) {
        for (int j = 0; j < n; j++) {
            std::cout << a[i][j] << " ";
        }
        std::cout << "\n";
    }
    return 0;
}