我会编写一个程序来打印s中最长的子字符串，其中字母按字母顺序出现。例如s = 'azcbobobegghakl'
将打印出'beggh'。
s = 'azcbobobegghakl'
result = ''
word ='a'
sen = ''
for alpha in s:
if alpha < word:
word ='a'
sen = ''
if alpha >= word:
word = alpha
sen += alpha
if len(result) <len(sen):
result = sen
print('Longest substring in alphabetical order is: '+ result)
答案是
Logest substring in alphabetical order is: beggh
但是只需将代码放在不同的行上。我的回答错了!!!
s = 'azcbobobegghakl'
result = ''
word ='a'
sen = ''
for alpha in s:
if alpha >= word:
word = alpha
sen += alpha
if len(result) <len(sen):
result = sen
if alpha < word:
word ='a'
sen = ''
print('Longest substring in alphabetical order is: '+ result)
回答
Longest substring in alphabetical order is: eggh
这个问题让我发疯了!!!
答案 0 :(得分：0)
您正在丢弃新序列的第一个字符
var SearchResultComponent = Vue.extend({
template:
'<div class="table-responsive">' +
'<h3 class="selectedItemsHeader" style="margin-top:0;margin-bottom:0;">{{ language.resultsItems }}</h3>' +
'<table class="table">' +
'<thead>' +
'<tr>' +
'<th style="width:15%">' +
'<a href="javascript:void(0)" style="color:#333;" class="sort-btn companyrate" @click="sortBy = \'rate\'">{{ language.company }} <i class="fa fa-caret-down"></i></a>' +
'</th>' +
'<th style="width:30%">{{ language.service }}</th>' +
'<th style="width:10%">{{ language.servicePrice }}</th>' +
'<th style="width:10%">{{ language.discount }}</th>' +
'<th style="width:15%">{{ language.info }}</th>' +
'<th style="width:10%">' +
'<a href="javascript:void(0)" class="sort-btn totalVat" @click="sortBy = \'total\'">{{ language.totalVat }} <i class="fa fa-caret-up"></i></a>' +
'</th>' +
'<th></th>' +
'</tr>' +
'</thead>' +
'<tbody v-if="items.length > 0">' +
'<tr v-for="item in items | orderBy itemByTotalPrice">' +
'<td class="clearfix">{{ item.companyName }}'+
'<span class="rate" v-if="item.companyRate"><span class="star"></span><span class="point">{{ item.companyRate }} / 5</span></span>'+
'</td>' +
'<td class="small-text item-name">{{{ getItemName(item) }}}</td>' +
'<td>{{ totalPriceNoDiscount(item) }} €</td>' +
'<td>{{ totalPriceDiscount(item) }} €</td>' +
'<td class="small-text">{{ item.companyNote || \' - \' }}</td>' +
'<td>{{ totalPrice(item) }} €</td>' +
'<td>'+
'<button class="btn btn-primary btn-sm" @click="select(item, $event)">{{ language.select }}</button>' +
'</td>' +
'</tr>' +
'</tbody>' +
'<tbody v-if="items.length == 0">' +
'<tr>' +
'<td colspan="7" style="font-size: 12pt;color: #777;padding-top: 60px;">{{ language.noResultsFound }}</td>' +
'</tr>' +
'</tbody>' +
'</table>' +
'<h3 class="selectedItemsHeader" v-if="selectedItems.length > 0">{{ language.selectedItems }}</h3>' +
'<table class="table selectedItems" v-if="selectedItems.length > 0">' +
'<tbody>' +
'<tr v-for="item in selectedItems">' +
'<td style="width:15%">{{ item.selectedItem.companyName }}' +
'</td>' +
'<td style="width:30%" class="small-text item-name">{{{ getItemName(item.selectedItem) }}}</td>' +
'<td style="width:10%">{{ totalPriceNoDiscount(item.selectedItem) }} €</td>' +
'<td style="width:10%">{{ totalPriceDiscount(item.selectedItem) || \'0.00\' }} €</td>' +
'<td style="width:15%" class="small-text">{{ item.selectedItem.companyNote || \' - \' }}</td>' +
'<td style="width:10%">{{ totalPrice(item.selectedItem) }} €</td>' +
'<td>'+
'<button class="btn btn-danger btn-sm" @click="remove(item)"><i class="fa fa-remove"></i></button>' +
'</td>' +
'</tr>' +
'</tbody>' +
'</table>' +
'</div>',
props: ['items','selectedItems','removeUrl'],
data: function(){ return { sortBy: 'total' } },
computed: {
'language' : function() { return language; }
},
methods: {
'select' : function(item, ev) {
this.$dispatch('onCompanySelect', item);
$(ev.target).attr('disabled', true).addClass('disabled');
},
'remove' : function(item) {
this.$dispatch('onSelectedItemRemove', {
removeUrl: this.removeUrl,
item: item
});
},
'totalPriceNoDiscount' : function(item) {
return item.priceNoDiscount.toFixed(2);
},
'totalPriceDiscount' : function(item) {
return (item.priceNoDiscount - this.totalPrice(item)).toFixed(2);
},
'totalPrice' : function(item) {
return item.extraServicesPriceVat ? (item.priceVat + item.extraServicesPriceVat).toFixed(2) : item.priceVat.toFixed(2);
},
'itemByTotalPrice' : function(a, b) {
if(this.sortBy == 'total') {
$('a.companyrate').css('color', '#333');
$('a.totalVat').css('color', '#337ab7');
return this.totalPrice(a) > this.totalPrice(b);
} else if(this.sortBy == 'rate') {
$('a.totalVat').css('color', '#333');
$('a.companyrate').css('color', '#337ab7');
return a.companyRate < b.companyRate;
}
}
}
});
注意改变：
s = 'azcbobobegghakl'
result = ''
word ='a'
sen = ''
for alpha in s:
print alpha,word,sen
if alpha >= word:
word = alpha
sen += alpha
if len(result) <len(sen):
result = sen
if alpha < word:
word = alpha
sen = alpha
print('Longest substring in alphabetical order is: '+ result)
你应该保存新序列的第一个字符
答案 1 :(得分：0)
好的，我们假设您有几个函数f1和f2，并且您正在跟踪for循环的每次迭代，如下所示：
def f1(s):
result = ''
word = 'a'
sen = ''
for index, alpha in enumerate(s):
if alpha < word:
word = 'a'
sen = ''
if alpha >= word:
word = alpha
sen += alpha
if len(result) < len(sen):
result = sen
print("{0}-{1} => {2}".format(index, alpha, result))
return result
def f2(s):
result = ''
word = 'a'
sen = ''
for index, alpha in enumerate(s):
if alpha >= word:
word = alpha
sen += alpha
if len(result) < len(sen):
result = sen
if alpha < word:
word = 'a'
sen = ''
print("{0}-{1} => {2}".format(index, alpha, result))
return result
s = 'azcbobobegghakl'
print('-' * 80)
print('f1: Longest substring in alphabetical order is: ' + f1(s))
print('-' * 80)
print('f2: Longest substring in alphabetical order is: ' + f2(s))
现在，运行此脚本将产生：
--------------------------------------------------------------------------------
0-a => a
1-z => az
2-c => az
3-b => az
4-o => az
5-b => az
6-o => az
7-b => az
8-e => az
9-g => beg
10-g => begg
11-h => beggh
12-a => beggh
13-k => beggh
14-l => beggh
f1: Longest substring in alphabetical order is: beggh
--------------------------------------------------------------------------------
0-a => a
1-z => az
2-c => az
3-b => az
4-o => az
5-b => az
6-o => az
7-b => az
8-e => az
9-g => az
10-g => egg
11-h => eggh
12-a => eggh
13-k => eggh
14-l => eggh
f2: Longest substring in alphabetical order is: eggh
正如你所看到的，一切都是相同的，直到它到达迭代9，f1结果变为9-g => beg而f2变为9-g => az，这就是顺序的变化如何影响结果，希望现在有意义。