执行加减命令后打印修改后的数组

给定一个大小为“n”的数组和一组给定的大小为“m”的命令。每个命令由四个整数 q、l、r、k 组成。这些命令有以下类型：

• 如果 q = 0，则将 'k' 添加到 'a' 到 'b' 范围内的所有整数（1 <= a <= b <= n）。
  
• 如果 q = 1，则将 'k' 减去 'a' 到 'b' 范围内的所有整数（1 <= a <= b <= n）。
  

注意：最初所有数组元素都设置为“0”，数组索引从“1”开始。

Input : n = 5
        commands[] = {{0 1 3 2}, {1 3 5 3}, 
                      {0 2 5 1}}
Output : 0 2 -1 -1 -3
Explanation
First command: Add 2 from index 1 to 3
>=  2 2 2 0 0
Second command: Subtract 3 from index 3 to 5 
>= 2 2 -1 -3 -3
Third command: Add 1 from index 2 to 5
>= 2 3 0 -2 -2

简单的方法是通过从左索引（l）到右索引（r）迭代来执行每个命令，并根据给定的命令更新每个索引。这种方法的时间复杂度是 O(n*m)
更好的方法是使用 Fenwick 树（BIT）或段树。但它只会优化到 log(n) 时间，即整体复杂度将变为 O(m*log(n))
有效的方法是使用简单的数学。由于所有命令都可以离线处理，因此我们可以将所有更新存储在临时数组中，然后最后执行。

• 对于命令“ 0 ”，分别在第 l^个和第(r+1)^个索引元素中添加“ +k ”和“ -k ”。
  
• 对于命令' 1 '，分别在第l^个和第(r+1)^个索引元素中添加' -k '和' +k '。
  

之后，总结从第一个索引开始的每个索引“ i ”的所有元素，即a _i将包含从第 1^个索引到第 i^个索引的所有元素的总和。这可以在动态规划的帮助下轻松实现。

C++

// C++ program to find modified array
// after executing m commands/queries
#include
using namespace std;
 
// Update function for every command
void updateQuery(int arr[], int n, int q, int l,
                 int r, int k)
{
    // If q == 0, add 'k' and '-k'
    // to 'l-1' and 'r' index
    if (q == 0){
        arr[l-1] += k;
        arr[r] += -k;
    }
 
    // If q == 1, add '-k' and 'k'
    // to 'l-1' and 'r' index
    else{
        arr[l-1] += -k;
        arr[r] += k;
    }
    return;
}
 
// Function to generate the final
// array after executing all
// commands
void generateArray(int arr[], int n)
{
    // Generate final array with the
    // help of DP concept
    for (int i = 1; i < n; ++i)
        arr[i] += arr[i-1];
     
    return;
}
 
// Driver program
int main()
{
    int n = 5;
    int arr[n+1];
    //Set all array elements to '0'
    memset(arr, 0, sizeof(arr));
 
    int q = 0, l = 1, r = 3, k = 2;
    updateQuery(arr, n, q, l, r, k);
 
    q = 1 , l = 3, r = 5, k = 3;
    updateQuery(arr, n, q, l, r, k);
 
    q = 0 , l = 2, r = 5, k = 1;
    updateQuery(arr, n, q, l, r, k);
 
    // Generate final array
    generateArray(arr, n);
 
    // Printing the final modified array
    for (int i = 0; i < n; ++i)
        cout << arr[i] << " ";
    return 0;
}

Java

// Java program to find modified array
// after executing m commands/queries
import java.util.Arrays;
 
class GFG {
     
    // Update function for every command
    static void updateQuery(int arr[], int n,
                  int q, int l, int r, int k)
    {
         
        // If q == 0, add 'k' and '-k'
        // to 'l-1' and 'r' index
        if (q == 0){
            arr[l-1] += k;
            arr[r] += -k;
        }
      
        // If q == 1, add '-k' and 'k'
        // to 'l-1' and 'r' index
        else{
            arr[l-1] += -k;
            arr[r] += k;
        }
         
        return;
    }
      
    // Function to generate the final
    // array after executing all
    // commands
    static void generateArray(int arr[], int n)
    {
        // Generate final array with the
        // help of DP concept
        for (int i = 1; i < n; ++i)
            arr[i] += arr[i-1];
          
    }
    //driver code
    public static void main(String arg[])
    {
        int n = 5;
        int arr[] = new int[n+1];
         
        //Set all array elements to '0'
        Arrays.fill(arr, 0);
         
        int q = 0, l = 1, r = 3, k = 2;
        updateQuery(arr, n, q, l, r, k);
      
        q = 1 ; l = 3; r = 5; k = 3;
        updateQuery(arr, n, q, l, r, k);
      
        q = 0 ; l = 2; r = 5; k = 1;
        updateQuery(arr, n, q, l, r, k);
      
        // Generate final array
        generateArray(arr, n);
      
        // Printing the final modified array
        for (int i = 0; i < n; ++i)
            System.out.print(arr[i]+" ");
    }
}
 
// This code is contributed by Anant Agarwal.

Python3

# Python3 program to find modified array
# after executing m commands/queries
 
# Update function for every command
def updateQuery(arr, n, q, l, r, k):
 
    # If q == 0, add 'k' and '-k'
    # to 'l-1' and 'r' index
    if (q == 0):
        arr[l - 1] += k
        arr[r] += -k
 
    # If q == 1, add '-k' and 'k'
    # to 'l-1' and 'r' index
    else:
        arr[l - 1] += -k
        arr[r] += k
     
    return
 
# Function to generate the final
# array after executing all commands
def generateArray(arr, n):
 
    # Generate final array with the
    # help of DP concept
    for i in range(1, n):
        arr[i] += arr[i - 1]
     
    return
 
# Driver Code
n = 5
arr = [0 for i in range(n + 1)]
 
# Set all array elements to '0'
q = 0; l = 1; r = 3; k = 2
updateQuery(arr, n, q, l, r, k)
 
q, l, r, k = 1, 3, 5, 3
updateQuery(arr, n, q, l, r, k);
 
q, l, r, k = 0, 2, 5, 1
updateQuery(arr, n, q, l, r, k)
 
# Generate final array
generateArray(arr, n)
 
# Printing the final modified array
for i in range(n):
    print(arr[i], end = " ")
     
     
# This code is contributed by Anant Agarwal.

C#

// Program to find modified
// array after executing
// m commands/queries
using System;
 
class GFG {
 
    // Update function for every command
    static void updateQuery(int[] arr, int n, int q,
                            int l, int r, int k)
    {
 
        // If q == 0, add 'k' and '-k'
        // to 'l-1' and 'r' index
        if (q == 0) {
            arr[l - 1] += k;
            arr[r] += -k;
        }
 
        // If q == 1, add '-k' and 'k'
        // to 'l-1' and 'r' index
        else {
            arr[l - 1] += -k;
            arr[r] += k;
        }
        return;
    }
 
    // Function to generate final
    // array after executing all
    // commands
    static void generateArray(int[] arr, int n)
    {
        // Generate final array with
        // the help of DP concept
        for (int i = 1; i < n; ++i)
            arr[i] += arr[i - 1];
    }
 
    // Driver code
    public static void Main()
    {
        int n = 5;
        int[] arr = new int[n + 1];
 
        // Set all array elements to '0'
        for (int i = 0; i < arr.Length; i++)
            arr[i] = 0;
 
        int q = 0, l = 1, r = 3, k = 2;
        updateQuery(arr, n, q, l, r, k);
 
        q = 1;
        l = 3;
        r = 5;
        k = 3;
        updateQuery(arr, n, q, l, r, k);
 
        q = 0;
        l = 2;
        r = 5;
        k = 1;
        updateQuery(arr, n, q, l, r, k);
 
        // Generate final array
        generateArray(arr, n);
 
        // Printing the final modified array
        for (int i = 0; i < n; ++i)
            Console.Write(arr[i] + " ");
    }
}
 
// This code is contributed by Anant Agarwal.

Javascript

// javascript program to find modified array
// after executing m commands/queries
 
    // Update function for every command
    function updateQuery(arr , n , q , l , r , k) {
 
        // If q == 0, add 'k' and '-k'
        // to 'l-1' and 'r' index
        if (q == 0) {
            arr[l - 1] += k;
            arr[r] += -k;
        }
 
        // If q == 1, add '-k' and 'k'
        // to 'l-1' and 'r' index
        else {
            arr[l - 1] += -k;
            arr[r] += k;
        }
 
        return;
    }
 
    // Function to generate the final
    // array after executing all
    // commands
    function generateArray(arr, n)
    {
     
        // Generate final array with the
        // help of DP concept
        for (i = 1; i < n; ++i)
            arr[i] += arr[i - 1];
 
    }
 
    // Driver code
        var n = 5;
        var arr = Array(n + 1).fill(0);
        var q = 0, l = 1, r = 3, k = 2;
        updateQuery(arr, n, q, l, r, k);
 
        q = 1;
        l = 3;
        r = 5;
        k = 3;
        updateQuery(arr, n, q, l, r, k);
 
        q = 0;
        l = 2;
        r = 5;
        k = 1;
        updateQuery(arr, n, q, l, r, k);
 
        // Generate final array
        generateArray(arr, n);
 
        // Printing the final modified array
        for (i = 0; i < n; i++)
            document.write(arr[i] + " ");
 
// This code is contributed by aashish1995

Output: 2 3 0 -2 -2