PASTER

参考代码

洛谷 P1601 高精度 A+B

#include <bits/stdc++.h>
using namespace std;
const int maxn = 505;
string s1, s2;
int a[maxn], b[maxn];
void read(string s, int n[]) {
    for (int i = 0; i < s.size(); ++i) {
        n[i] = s[s.size() - i - 1] - '0';
    }
}
void add() {
    for (int i = 0; i <= 500; ++i) {
        a[i] = a[i] + b[i];
        while (a[i] >= 10) {
            a[i] -= 10;
            a[i + 1]++;
        }
    }
}
void print() {
    int p = 501;
    while (p >= 0 && a[p] == 0) p--;
    if (p < 0) {
        cout << 0;
    }
    while (p >= 0) cout << a[p--];
    cout << endl;
}
int main()
{
    cin >> s1 >> s2;
    read(s1, a), read(s2, b);
    add();
    print();
    return 0;
}

一本通 1169 高精度 A-B

#include <bits/stdc++.h>
using namespace std;
const int maxn = 505;
string s1, s2;
int a[maxn], b[maxn];
void read(string s, int n[]) {
    for (int i = 0; i < s.size(); ++i) {
        n[i] = s[s.size() - i - 1] - '0';
    }
}
void add() {
    for (int i = 0; i <= 500; ++i) {
        a[i] = a[i] + b[i];
        while (a[i] >= 10) {
            a[i] -= 10;
            a[i + 1]++;
        }
    }
}
void minu() {
    for (int i = 0; i <= 500; ++i) {
        a[i] = a[i] - b[i];
        while (a[i] < 0) {
            a[i] += 10;
            a[i + 1]--;
        }
    }
}
void print() {
    int p = 501;
    while (p >= 0 && a[p] == 0) p--;
    if (p < 0) {
        cout << 0;
    }
    while (p >= 0) cout << a[p--];
    cout << endl;
}
int main()
{
    cin >> s1 >> s2;
    read(s1, a), read(s2, b);
    minu();
    print();
    return 0;
}

一本通 1172 高精度阶乘

#include <bits/stdc++.h>
using namespace std;
const int maxn = 50005;
string s1, s2;
int a[maxn], b[maxn], c[maxn];
void read(string s, int n[]) {
    for (int i = 0; i < s.size(); ++i) {
        n[i] = s[s.size() - i - 1] - '0';
    }
}
void add(int a[], int b[]) {
    for (int i = 0; i < maxn / 2; ++i) {
        a[i] = a[i] + b[i];
        a[i + 1] += a[i] / 10;
        a[i] %= 10; 
    }
}
void minu(int a[], int b[]) {
    for (int i = 0; i < maxn / 2; ++i) {
        a[i] = a[i] - b[i];
        while (a[i] < 0) {
            a[i] += 10;
            a[i + 1]--;
        }
    }
}
void print(int a[]) {
    int p = maxn;
    while (p >= 0 && a[p] == 0) p--;
    if (p < 0) {
        cout << 0;
    }
    while (p >= 0) cout << a[p--];
    cout << endl;
}
int main() {
    int n;
    cin >> n;
    a[0] = 1;
    int weishu = 0;
    for (int i = 2; i <= n; ++i) {
        for (int j = 0; j <= weishu; ++j) {
            a[j] = a[j] * i;
        }
        for (int j = 0; j < weishu + 5; ++j) {
            if (a[j] >= 10) {
                weishu = j + 1;
            }
            if (a[j] >= 10) {
                a[j + 1] += a[j] / 10;
                a[j] = a[j] % 10;
            }
        }
    }
    print(a);
}

一本通 1171 大整数因子

#include <bits/stdc++.h>
using namespace std;
const int maxn = 50005;
string s1, s2;
int a[maxn], b[maxn];
void print(int a[]) {
    int p = maxn;
    while (p >= 0 && a[p] == 0) p--;
    if (p < 0) {
        cout << 0;
    }
    while (p >= 0) cout << a[p--];
    cout << endl;
}
int main() {
    cin >> s1;
    bool flag = 0;
    int len = s1.size();
    for (int k = 2; k <= 9; ++k) {
        int mod = 0;
        for (int i = 0; i < len; ++i) {
            mod = (mod * 10 + (s1[i] - '0')) % k;
        }
        if (!mod) {
            cout << k << " ";
            flag = 1;
        }
    }
    if (!flag) cout << "none";
    cout << endl;
}

一本通 1181 整数奇偶排序

#include <bits/stdc++.h>
using namespace std;
const int maxn = 15;
int a[maxn];
int b[maxn];
void bubble_sort1(int l, int r) {
    for (int i = 0; i < r - l + 1; ++i) {
        for (int j = l; j < r; ++j) {
            if (b[j] > b[j + 1]) {
                swap(b[j], b[j + 1]);
            }
        }
    }
}
void bubble_sort2(int l, int r) {
    for (int i = 0; i < r - l + 1; ++i) {
        for (int j = l; j < r; ++j) {
            if (b[j] < b[j + 1]) {
                swap(b[j], b[j + 1]);
            }
        }
    }
}
signed main()
{
    for (int i = 0; i < 10; ++i) {
        cin >> a[i];
    }
    int p1 = 0, p2 = 9;
    for (int i = 0; i < 10; ++i) {
        if (a[i] % 2 == 0) {
            b[p2] = a[i];
            p2--;
          }
        else {
            b[p1] = a[i];
                p1++;
         }
       }
    bubble_sort2(0, p1 - 1);
    bubble_sort1(p1, 9);
    for (int i = 0; i < 10; ++i)
        cout << b[i] << " ";
    cout << endl;
    return 0;
}

一本通 1184 明明的随机数（去重与排序）

#include <bits/stdc++.h>
using namespace std;
const int maxn = 15;
bool v[1001];
int a[105];
int b[105];
void bubble_sort(int l, int r) {
    for (int i = 0; i < r - l + 1; ++i) {
        for (int j = l; j < r; ++j) {
            if (b[j] > b[j + 1]) {
                swap(b[j], b[j + 1]);
            }
        }
    }
}
signed main()
{
    int n;
    cin >> n;
    for (int i = 0; i < n; ++i) {
        cin >> a[i];
    }
    int p = 0;
    for (int i = 0; i < n; ++i) {
        if (!v[a[i]]) {
            v[a[i]] = 1;
            b[p] = a[i];
            p++;
        }
    }
    bubble_sort(0, p - 1);
    cout << p << endl;
    for (int i = 0; i < p; ++i) {
        cout << b[i] << " ";
    }
    cout << endl;
    return 0;
}

P1177 【模板】快速排序

#include <bits/stdc++.h>
using namespace std;
const int maxn = 1e5 + 5;
int a[maxn];
void quick_sort(int l, int r) {
    if(r <= l) {
        return;
    }
    int i = l, j = r;
    int mid = a[(l + r) >> 1];
    while(i <= j){
        while(a[i] < mid) i++;
        while(a[j] > mid) j--;
        if(i <= j){
            swap(a[i], a[j]);
            i++;
            j--;
        }
    }
    quick_sort(l, j);
    quick_sort(i, r);
}
int main()
{
    int n;
    cin >> n;
    for (int i = 1; i <= n; ++i) cin >> a[i];
    quick_sort(1, n);
    for (int i = 1; i <= n; ++i) cout << a[i] << ' ';
    return 0;
}

P1223 排队接水 贪心+排序

#include <bits/stdc++.h>
using namespace std;
const int maxn =1005;
struct node {
    int x, id;
    bool operator < (const node & y) {
        return x < y.x;
    }
}a[maxn];
int main()
{
    ios::sync_with_stdio(0);
    cin.tie(0);
    int n;
    cin >> n;
    for (int i = 1; i <= n; ++i) a[i].id = i, cin >> a[i].x;
    sort(a + 1, a + 1 + n);
    for (int i = 1; i <= n; ++i) cout << a[i].id << " ";
    cout << endl;
    double ans = 0;
    for (int i = 1; i < n; ++i) {
        ans += (n - i) * a[i].x;
    }
    ans /= n;
    cout << fixed << setprecision(2) << ans << endl;
    return 0;
}

归并排序模板

#include <bits/stdc++.h>
using namespace std;
const int maxn = 1e5 + 5;
int a[maxn];
int b[maxn];
void merge_sort(int l, int r) {
    if (l == r) return;
    int mid = (l + r) / 2;
    merge_sort(l, mid);
    merge_sort(mid + 1, r);
    int p1 = l, p2 = mid + 1, p3 = l;
    while (p1 <= mid || p2 <= r) {
        if (p1 <= mid && p2 <= r) {
            if (a[p1] < a[p2]) {
                b[p3] = a[p1];
                p3++; p1++;
            }
            else {
                b[p3] = a[p2];
                p3++; p2++;
            }
        }
        else if (p1 <= mid) {
            b[p3] = a[p1];
            p3++; p1++;
        }
        else {
            b[p3] = a[p2];
            p3++; p2++;
        }
    }
    for (int i = l; i <= r; ++i) a[i] = b[i];
}
int main()
{
    int n;
    cin >> n;
    for (int i = 1; i <= n; ++i) cin >> a[i];
    merge_sort(1, n);
    for (int i = 1; i <= n; ++i) cout << a[i] << ' ';
    return 0;
}