这里我编写了一个代码，用于在不使用strtok（）函数的情况下将单词与给定句子分开。但问题是它只打印第一个单词。为什么其余的单词都不打印？
#include <stdio.h>
#include <string.h>
int main ()
{
char str[] ="This, a sample string.";
int i=0,k,begin,end;
while(str[i]!='\0'){
while(str[i]==' '){
i++;
}
begin = i;
while(str[i]!=' ' && str[i]!='\0'){
i++;
}
end = i-1;
char *ptr =(char *)malloc((end-begin)*sizeof(char));
for(k=begin;k<=end;k++){
ptr[k] = str[k];
}
printf("%s\n",ptr);
if(str[i]=='\0'){
break;
}
}
}
答案 0 :(得分：1)
完整的代码应该是这样的。
我在代码之上更改了代码。
int main ()
{
char str[] ="This, a sample string.";
int i=0,k,begin,end;
int t;
while(str[i]!='\0'){
begin = i;
while(str[i]!=' ' && str[i]!='\0'){
i++;
}
end = i-1;
char *ptr = (char *) malloc( (i-begin)*sizeof(char) + 1);
t=0;
for(k=begin;k<=end;k++){
ptr[t++] = str[k];
}
ptr[t] = '\0';
puts(ptr);
if(str[i]=='\0'){
break;
} else
while(str[i] == ' ') i++; //To avoid multiple spaces
}
return 0;
}
-Thanks
答案 1 :(得分：1)
您的代码存在问题：
k ptr被用作str和end - begin + 1的索引变量，你应该做的是为ptr使用一个单独的变量，这样它就可以填充0索引中的字符
此外，您没有分配正确的空间。字符数为null character，您还必须为char *ptr =(char *)malloc((end-begin+2)*sizeof(char));
（字符串终止字符）分配空间。
所以正确的分配是：
int index = 0;
for(k = begin;k <= end; k++){
ptr[jj++] = str[k];
}
ptr[end - begin + 1] = '\0';
，您的正确代码是：
<link href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/css/bootstrap.min.css" rel="stylesheet" />
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.12.4/jquery.min.js"></script>
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/js/bootstrap.min.js"></script>
<div id="TABBEDLOCATEPANEL" ng-show="locate.toggleCheck()" class="container">
<div id=locatePanel class="row">
<div class="col-md-4 col-sm-3 col-xs-3">
<div class="tabs-left">
<ul id=locateTabs class="nav form-tabs nav-pills nav-stacked">
<li class="active" title="Locate By Address">
<a data-toggle="pill" href="#locateTab1" target='_self'><img src="images/Address.png" height="30" width="30"></a>
</li>
<li title="Locate By Existing Record">
<a data-toggle="pill" href="#locateTab2" target='_self'><img src="images/entity.png" height="30" width="30"></a>
</li>
<li title="Locate By Coordinate">
<a data-toggle="pill" href="#locateTab3" target='_self'><img src="images/coordinator.png" height="30" width="30"></a>
</li>
<li title="Geography" ng-show="locate.getJSON().geographyTab" ng-click="locate.showGeographyData();">
<a data-toggle="pill" href="#locateTab4" target='_self'><img src="images/geography.png" height="30" width="30"></a>
</li>
<li title="Results" id="ltab5" ng-show="locate.resultsTab">
<a data-toggle="pill" href="#locateTab5" target='_self'><img src="images/Result.png" height="30" width="30"></a>
</li>
</ul>
</div>
</div>
<div class="col-md-8 col-sm-9 col-xs-9">
<div class="tab-content">
<div id="locateTab1" class="tab-pane active">
<table id=locateAddress style="border-collapse: separate; border-spacing: 5px;">
<div class="field-container">
<input type='text' class="field" name=locatebyaddress_address ng-model="locate.locatebyaddress_address" required placeholder="Address" init-from-form>
<label class="floating-label">Address:</label>
<div class="field-underline"></div>
</div>
<div class="field-container">
<input type='text' class="field" name=locatebyaddress_city ng-model="locate.locatebyaddress_city" required placeholder="City" init-from-form>
<label class="floating-label">City:</label>
<div class="field-underline"></div>
</div>
<div class="field-container">
<input type='text' class="field" name=locatebyaddress_state ng-model="locate.locatebyaddress_state" required placeholder="State" init-from-form>
<label class="floating-label">State:</label>
<div class="field-underline"></div>
</div>
<div class="field-container">
<input type='text' class="field" name=locatebyaddress_zip ng-model="locate.locatebyaddress_zip" required placeholder="Zip" init-from-form>
<label class="floating-label">Zip:</label>
<div class="field-underline"></div>
</div>
<div class="field-container">
<input type='text' class="field" name=locatebyaddress_longitude disabled=disabled ng-model="locate.locatebyaddress_longitude" required placeholder="Longitude" init-from-form>
<label class="floating-label">Longitude:</label>
<div class="field-underline"></div>
</div>
<div class="field-container">
<input type='text' class="field" name=locatebyaddress_latitude disabled=disabled ng-model="locate.locatebyaddress_latitude" required placeholder="Latitude" init-from-form>
<label class="floating-label">Latitude:</label>
<div class="field-underline"></div>
</div>
</table>
<br>
<input type=submit value=Find id=locateByAddress ng-click="locate.locateByAddress();">
<input type=button ng-click="locate.zoomToLocation();" ng-disabled="locate.entityDisabledCheck" ng-class="{'disabledButton':locate.isDisabledActive}" value="Zoom" id=zoomtolocation>
<input type=reset value=Cancel ng-click="locate.destroyLocatePanel();" id=cancelLocate>
</div>
<div id="locateTab2" class="tab-pane">
<table id=locateRecord style="border-collapse: separate; border-spacing: 5px;">
<tr>
<td>Entity Type</td>
<td>
<select id=locateEntityType ng-change="locate.entityChanged();" ng-model="locate.entityType">
<option></option>
<option ng-repeat="(key, value) in locate.getJSON().dropdown" value="{{key}}">{{ value }}</option>
</select>
</td>
</tr>
<tr>
<td>Record Number</td>
<td>
<input id=recordNumberExistingRecord ng-model="locate.recordNumber" type=text name=recordNumber>
</td>
</tr>
</table>
<br>
<input type=submit value=Find id=locateByExistingRecord ng-click="locate.getLocationByEntity();">
<input type=button ng-click="locate.zoomToLocation();" ng-disabled="locate.entityDisabledCheck" ng-class="{'disabledButton':locate.isDisabledActive}" value="Zoom" id=zoomtolocation>
<input type=reset value=Cancel ng-click="locate.destroyLocatePanel();" id=cancelLocate>
</div>
<div id="locateTab3" class="tab-pane">
<table id=locateCoordinates style="border-collapse: separate; border-spacing: 5px;">
<tr>
<td>Longitude</td>
<td>
<input type=text ng-model=locate.locateByCoordinatelongitude>
</td>
</tr>
<tr>
<td>Latitude</td>
<td>
<input type=text ng-model=locate.locateByCoordinatelatitude>
</td>
</tr>
<tr>
<td></td>
<td>
<input type=button ng-click="locate.pickCoordinate();" id=coordinatePick name=locatePick value=PICK>
</td>
</tr>
</table>
<br>
<input type=submit value=Find id=locateByCoordinate ng-click="locate.locateByCoordinate();">
<input type=button ng-click="locate.zoomToLocation();" ng-disabled="locate.entityDisabledCheck" ng-class="{'disabledButton':locate.isDisabledActive}" value="Zoom" id=zoomtolocation>
<input type=reset value=Cancel ng-click="locate.destroyLocatePanel();" id=cancelLocate>
<input type=button ng-click="locate.streetView();" ng-show="locate.streetViewCheck" value="Street View" id=streetView>
</div>
<div id="locateTab4" class="tab-pane" ng-show="locate.getJSON().geographyTab">
<div ng-html-compile="locate.getGeographyHTML()" | trust></div>
</div>
<div id="locateTab5" class="tab-pane" ng-show="locate.resultsTab">
<ul class="listAddress">
<li ng-repeat="list in locate.addressList" ng-click="locate.addressListClick($index);">
{{ list.formatted_address }}
</li>
</ul>
</div>
<!-- /result tab -->
</div>
<!-- /tab-content -->
</div>
<!-- /tabbable -->
</div>
<!-- /col -->
</div>
<!-- /row -->
</div>
<!-- /container -->答案 2 :(得分：0)
如果允许您就地修改字符串，则可以执行类似
的操作#include <stdio.h>
static void print_words(char *str) {
char *start = str; // Word start pointer.
for(;*str;str++) { // While there are characters...
if(*str == ' ') { // Space found!
*str = '\0'; // Replace the space with a null to end the string
printf("%s\n", start); // Output the now null-delimited string
*str = ' '; // Return the string to its original form
start = str + 1; // Advance the word-start pointer
}
}
printf("%s\n", start); // Print the last word remaining unprinted, if any
}
int main()
{
char str[] = "This, a sample string.";
print_words(str);
}
答案 3 :(得分：0)
您错过了代码中的一些逻辑。
默认情况下，您正在遍历第二个字。这不是你的要求。
此块标识来自给定字符串的单词。
** 4。 ptr [k] = str [k] 这是代码中的漏洞。
这应该像ptr [0] = str [k]; **
==================第1点=======================
while(str[i]!='\0'){
while(str[i]==' '){ -> this is point no 1. This logic will skip first word
i++;
}
=================point 2 ================
begin = i;
while(str[i]!=' ' && str[i]!='\0'){
i++;
}
**end = i-1;**
==========================================
char *ptr =(char *)malloc((end-begin)*sizeof(char)); -> point 3.
point 4 :
for(k=begin;k<=end;k++){
ptr[k] = str[k];
}
printf("%s\n",ptr);
if(str[i]=='\0'){
break;
}
point 5 :
else
i++;
}
-Thanks
答案 4 :(得分：0)
我找到了问题并提出了解决方案：
1.第一个问题是我没有为*ptr分配正确的值。所以，我使用变量j从当前索引的开头开始
2.我需要null终止每次捕获
ptr[k]='\0';
3.所以我总体上做出的改变如下：
for(k=0,j=begin;k<=end-begin;k++,j++){ // use a variable j to start from the beginning of current index
ptr[k] = str[j];
}
ptr[k]='\0';
完整代码：
#include <stdio.h>
#include <string.h>
int main ()
{
char str[] ="This, an sample string.";
int i=0,j,k,begin,end;
char *ptr;
while(str[i]!='\0'){
while(str[i]==' '){
i++;
}
begin = i;
while(str[i]!=' ' && str[i]!='\0'){
i++;
}
end = i-1;
ptr =(char *)malloc((end-begin)*sizeof(char));
for(k=0,j=begin;k<=end-begin;k++,j++){ // use a variable j to start from the beginning of current index
ptr[k] = str[j];
}
ptr[k]='\0';
printf("%s\n",ptr);
if(str[i]=='\0'){
break;
}
}
}