给定由N个唯一的小写字母和长度N的数组arr []组成的字符串S ，其中字符S [i]表示灯泡， arr [i]表示第i个灯泡发光的时间，从时间arr开始[i – 1] 。任务是找到发光时间最长的灯泡。如果存在一个以上的灯泡，且其最大发光时间相同，则按词典顺序打印一个更大的灯泡。
例子：
Input: S = “abcd”, arr[] = {9, 29, 49, 50}
Output: c
Explanation:
‘c’ at index 0 has a duration = 9.
‘b’ at index 1 has a duration = arr[1] – arr[0] = 29 – 9 = 20
‘c’ at index 2 has a duration = arr[2] – arr[1]= 49 – 29 = 20
‘d’ at index 3 has a duration = arr[3] – arr[2]= 50 – 49 = 1
Two bulbs, ‘b’ and ‘c’, have the maximum glowing time. Among those two, ‘c’ is lexicographically larger.
Input: S = “spuda”, arr[] = {12, 23, 36, 46, 62}
Output: a
Explanation:
‘s’ at index 0 has a duration = 12.
‘p’ at index 1 has a duration = arr[1] – arr[0] = 23-12 = 11.
‘u’ at index 2 has a duration = arr[2] – arr[1] = 36-23 = 13.
‘d’ at index 3 has a duration = arr[3] – arr[2] = 46-36 = 10.
‘a’ at index 4 has a duration = arr[4] – arr[3] = 62-46 = 16.
Therefore, ‘a’ has maximum glowing time.
方法：想法是遍历数组，并为每个数组元素计算arr [i] – arr [i – 1] 。然后，打印具有最大发光时间的按字典顺序排列的大灯泡。请按照以下步骤解决问题：
- 初始化两个变量，例如maxDur和maxPos ，以分别存储发光时间和具有最大发光时间的灯泡索引。
- 遍历给定数组并执行以下步骤：
- 如果当前时间(arr [i] – arr [i – 1])小于maxCurr ，则将maxCurr更新为maxCurr = arr [i] – arr [i – 1] 。
- 否则，如果它等于maxCurr，maxPos不包含任何有效的索引和S [maxPos]按字典顺序小于S [I]，更新maxPos如maxPos = I。
- 完成上述步骤后，将S [maxPos]打印为所需的输出。
下面是上述方法的实现：
C++
// C++ program for the above approach
#include
using namespace std;
// Function to find the bulb
// having maximum glow
char longestLastingBulb(
vector onTime, string s)
{
char ans;
int n = onTime.size();
// Initialize variables
int maxDur = INT_MIN;
int maxPos = INT_MIN;
int currentDiff = 0;
// Traverse the array consisting
// of glowing time of the bulbs
for (int i = 0; i < n; i++) {
// For 1st bulb
if (i == 0) {
currentDiff = onTime[i];
maxDur = currentDiff;
maxPos = i;
}
else {
// Calculate the glowing time
currentDiff = onTime[i]
- onTime[i - 1];
// Update the maximum glow
if (maxDur < currentDiff) {
maxDur = currentDiff;
maxPos = i;
}
// Find lexicographically
// largest bulb
else {
if (maxDur == currentDiff) {
char one = s[i];
char two = s[maxPos];
if (one > two) {
maxDur = currentDiff;
maxPos = i;
}
}
}
}
}
// Bulb with maximum time
ans = s[maxPos];
// Return the resultant bulb
return ans;
}
// Driver Code
int main()
{
string S = "spuda";
vector arr = { 12, 23, 36, 46, 62 };
// Function call
cout << longestLastingBulb(arr, S);
return 0;
} Java
// Java program for the above approach
import java.util.*;
class GFG{
// Function to find the bulb
// having maximum glow
static char longestLastingBulb(
int []onTime, char []s)
{
char ans;
int n = onTime.length;
// Initialize variables
int maxDur = Integer.MIN_VALUE;
int maxPos = Integer.MIN_VALUE;
int currentDiff = 0;
// Traverse the array consisting
// of glowing time of the bulbs
for (int i = 0; i < n; i++) {
// For 1st bulb
if (i == 0) {
currentDiff = onTime[i];
maxDur = currentDiff;
maxPos = i;
}
else {
// Calculate the glowing time
currentDiff = onTime[i]
- onTime[i - 1];
// Update the maximum glow
if (maxDur < currentDiff) {
maxDur = currentDiff;
maxPos = i;
}
// Find lexicographically
// largest bulb
else {
if (maxDur == currentDiff) {
char one = s[i];
char two = s[maxPos];
if (one > two) {
maxDur = currentDiff;
maxPos = i;
}
}
}
}
}
// Bulb with maximum time
ans = s[maxPos];
// Return the resultant bulb
return ans;
}
// Driver Code
public static void main(String[] args)
{
String S = "spuda";
int []arr = { 12, 23, 36, 46, 62 };
// Function call
System.out.print(longestLastingBulb(arr, S.toCharArray()));
}
}
// This code is contributed by Amit KatiyarPython3
# Python3 program for the above approach
import sys
INT_MIN = (sys.maxsize - 1)
# Function to find the bulb
# having maximum glow
def longestLastingBulb(onTime, s):
n = len(onTime)
# Initialize variables
maxDur = INT_MIN
maxPos = INT_MIN
currentDiff = 0
# Traverse the array consisting
# of glowing time of the bulbs
for i in range(n):
# For 1st bulb
if (i == 0):
currentDiff = onTime[i]
maxDur = currentDiff
maxPos = i
else:
# Calculate the glowing time
currentDiff = onTime[i] - onTime[i - 1]
# Update the maximum glow
if (maxDur < currentDiff):
maxDur = currentDiff
maxPos = i
# Find lexicographically
# largest bulb
else:
if (maxDur == currentDiff):
one = s[i]
two = s[maxPos]
if (one > two):
maxDur = currentDiff
maxPos = i
# Bulb with maximum time
ans = s[maxPos]
# Return the resultant bulb
return ans
# Driver Code
if __name__ == "__main__" :
S = "spuda"
arr = [ 12, 23, 36, 46, 62 ]
# Function call
print(longestLastingBulb(arr, S))
# This code is contributed by AnkThonC#
// C# program for the above approach
using System;
using System.Collections.Generic;
class GFG {
// Function to find the bulb
// having maximum glow
static char longestLastingBulb(
List onTime, string s)
{
char ans;
int n = onTime.Count;
// Initialize variables
int maxDur = Int32.MinValue;
int maxPos = Int32.MinValue;
int currentDiff = 0;
// Traverse the array consisting
// of glowing time of the bulbs
for (int i = 0; i < n; i++) {
// For 1st bulb
if (i == 0) {
currentDiff = onTime[i];
maxDur = currentDiff;
maxPos = i;
}
else {
// Calculate the glowing time
currentDiff = onTime[i]
- onTime[i - 1];
// Update the maximum glow
if (maxDur < currentDiff) {
maxDur = currentDiff;
maxPos = i;
}
// Find lexicographically
// largest bulb
else {
if (maxDur == currentDiff) {
char one = s[i];
char two = s[maxPos];
if (one > two) {
maxDur = currentDiff;
maxPos = i;
}
}
}
}
}
// Bulb with maximum time
ans = s[maxPos];
// Return the resultant bulb
return ans;
}
static void Main() {
string S = "spuda";
List arr = new List(new int[] {12, 23, 36, 46, 62});
// Function call
Console.Write(longestLastingBulb(arr, S));
}
}
// This code is contributed by divyeshrabadiya07 输出：
a时间复杂度： O(N)
辅助空间： O(1)