题解 | 【模板】差分

#include <iostream>
#include <vector>
using namespace std;

int main() {
    ios::sync_with_stdio(false);
    cin.tie(0);
    
    int n, m;
    cin >> n >> m;
    
    // 读入原数组
    vector<long long> a(n + 2, 0);  // 多开一个位置
    for(int i = 1; i <= n; i++) {
        cin >> a[i];
    }
    
    // 构建差分数组
    vector<long long> diff(n + 2, 0);
    for(int i = 1; i <= n; i++) {
        diff[i] = a[i] - a[i-1];
    }
    
    // 处理修改操作
    while(m--) {
        int l, r;
        long long k;
        cin >> l >> r >> k;
        diff[l] += k;
        diff[r + 1] -= k;
    }
    
    // 还原数组并输出
    for(int i = 1; i <= n; i++) {
        a[i] = a[i-1] + diff[i];
        cout << a[i] << (i == n ? '\n' : ' ');
    }
    
    return 0;
}

import java.io.*;
import java.util.*;

public class Main {
    public static void main(String[] args) throws IOException {
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        PrintWriter out = new PrintWriter(System.out);
        
        String[] line = br.readLine().split(" ");
        int n = Integer.parseInt(line[0]);
        int m = Integer.parseInt(line[1]);
        
        // 读入原数组
        long[] a = new long[n + 2];  // 多开一个位置
        line = br.readLine().split(" ");
        for(int i = 1; i <= n; i++) {
            a[i] = Long.parseLong(line[i-1]);
        }
        
        // 构建差分数组
        long[] diff = new long[n + 2];
        for(int i = 1; i <= n; i++) {
            diff[i] = a[i] - a[i-1];
        }
        
        // 处理修改操作
        while(m-- > 0) {
            line = br.readLine().split(" ");
            int l = Integer.parseInt(line[0]);
            int r = Integer.parseInt(line[1]);
            long k = Long.parseLong(line[2]);
            diff[l] += k;
            diff[r + 1] -= k;
        }
        
        // 还原数组并输出
        StringBuilder sb = new StringBuilder();
        for(int i = 1; i <= n; i++) {
            a[i] = a[i-1] + diff[i];
            sb.append(a[i]).append(i == n ? '\n' : ' ');
        }
        out.print(sb);
        out.flush();
    }
}

def main():
    n, m = map(int, input().split())
    
    # 读入原数组
    a = [0] * (n + 2)  # 多开一个位置
    nums = list(map(int, input().split()))
    for i in range(1, n + 1):
        a[i] = nums[i-1]
    
    # 构建差分数组
    diff = [0] * (n + 2)
    for i in range(1, n + 1):
        diff[i] = a[i] - a[i-1]
    
    # 处理修改操作
    for _ in range(m):
        l, r, k = map(int, input().split())
        diff[l] += k
        diff[r + 1] -= k
    
    # 还原数组并输出
    for i in range(1, n + 1):
        a[i] = a[i-1] + diff[i]
    print(*a[1:n+1])

if __name__ == "__main__":
    main()