请教：怎么把字符型数据转换成整型数据

[bonn]

老师布置的作业：怎么把一串字符型数据string[]="1-5,34,45,101-126"转换为整型数据输出1，2，3，4，5，34，45，101，102……126？

[ssbull]

#include <string>
#include <iostream>
using namespace std;
void main() {
string str[]={"1","2","3","4"};
int i[4];
for(int j=0;j<4;j++){
i[j]=atoi(str[j].c_str())+1;
cout<<i[j]<<" ";
}
cout<<endl;
}
output:
2 3 4 5
以上就把字符串转化为整型数据

[scale8292]

用atoi()函数试试

[lingar]

‘字符’-‘0’就是整型数据了

[buaaaladdin]

用strtok分割字符串，用atoi转换成整数。

遇到‘-’的时候就把左边和右边之间的数字打印出来就可以了，否则就直接打印。

[bonn]

那请问一下，具体这个atoi的函数是怎么应用，我没有看到过！

[ccwwbb]

#include <string>
#include <iostream>
using namespace std;
void main()
{
char *str[]={"1","2","3","4","5","43","45",
"101","102","103","104","105","106","107",
"108","109","110","111","112","113","114",
"115","116","117","118","119","120","121",
"122","123","124","125","126"};
char **p;
p=str;
for(int i=0;i<33;i++)
cout<<atoi(*(p+i))<<" ";

[ccwwbb]

少了最后一个
}；

[ccwwbb]

#include <string>
#include <iostream>
using namespace std;
void main()
{
char *str[]={"1","2","3","4","5","43","45",
"101","102","103","104","105","106","107",
"108","109","110","111","112","113","114",
"115","116","117","118","119","120","121",
"122","123","124","125","126"};
char **p;
p=str;
for(int i=0;i<33;i++)
cout<<atoi(*(p+i))<<" ";
}

[pxwzd123]

#include <stdlib.h>
#include <stdio.h>

void main( void )
{
char *s; double x; int i; long l;

s = " -2309.12E-15"; /* Test of atof */
x = atof( s );
printf( "atof test: ASCII string: %s\tfloat: %e\n", s, x );

s = "7.8912654773d210"; /* Test of atof */
x = atof( s );
printf( "atof test: ASCII string: %s\tfloat: %e\n", s, x );

s = " -9885 pigs"; /* Test of atoi */
i = atoi( s );
printf( "atoi test: ASCII string: %s\t\tinteger: %d\n", s, i );

s = "98854 dollars"; /* Test of atol */
l = atol( s );
printf( "atol test: ASCII string: %s\t\tlong: %ld\n", s, l );
}

[ssbull]

atoi()函数的使用方法很简单。（）中填入你要进行转换的字符串就可以了，注意，这个参数要是const char *型的

[bapldc]

请问函数的递归怎么用的？

[TianGuangZao]

#include <stdio.h>

int main()
{
char *str[33]= {"1","2","3","4","5","43","45",
"101","102","103","104","105","106","107",
"108","109","110","111","112","113","114",
"115","116","117","118","119","120","121",
"122","123","124","125","126"};

int iarr[33] = {0};
int i;
for ( i = 0; i < 33; i++)
{
sscanf( str[i], "%d", &iarr[i]);
printf( "%d\n", iarr[i]);
}
return 0;
}

用 sscanf 也可以。

[Andy84920]

agree to pxwzd123(tajore) .

end.

[yeyuboy]

agree with scale8292

[bonn]

倒~~~其实是要你输入此类任意类型的字符型数据，然后进行转换

[jakeye]

‘字符’-‘0’就是整型数据了
取字符串中的每一个字符然后一字符‘0’，就可以了....。简单吧


接分喽！！！

[bonn]

我都不知道怎么给分了，这么多兄弟捧场

[brxren]

我给你个程序,我做的!
#include <iostream>
using namespace std;
#include <vector>
#include <string>

void intToChar(vector <int> save,vector <char> &output)
{
int tiaoyue=1;//tiaoyue是用来解决读取几个不连续的值的问题，此鉴别方法有待改进！！！
int i;
if(save[0]/10!=0)
output.push_back(char(save[0]/10+48));
output.push_back(char(save[0]%10+48));
for(i=1;i<save.size();i++)
{
if((save[i]-save[i-1])==1)
{
if(i==(save.size()-1))
{
output.push_back('-');
if(save[i]/10!=0)
output.push_back(char(save[i]/10+48));
output.push_back(char(save[i]%10+48));
}
tiaoyue=0;
}
else
{
tiaoyue++;
if(tiaoyue==1)
{
output.push_back('-');
if(save[i-1]/10!=0)
output.push_back(char(save[i-1]/10+48));
output.push_back(char(save[i-1]%10+48));
}
output.push_back(',');
if(save[i]/10!=0)
output.push_back(char(save[i]/10+48));
output.push_back(char(save[i]%10+48));
}
}

}


int stringToDeci(vector <char> buf)
{
int i=0;
int sum=0;
while(i<buf.size()) sum=sum*10+buf[i++]-48;
return sum;
}

void perform(vector <char> start,vector <char> end,vector <int> &save)
{
int i;
int min=stringToDeci(start);
int max=stringToDeci(end);
for(i=min;i<=max;i++)
{
save.push_back(i);
}
}

void ReadThrough(vector <int> &save,string input)//用来挨个读取input里的内容
{
int flag=0;//flag是用来记录读取的值是表示一个区间的最小值还是表示一个区间的最大值，
//flag=0表示是最小值，flag=1表示是最大值
vector <char> start; //存储表示最小值的字符串
vector <char> end;//存储表示最大值的字符串
char *p;
p=&input[0];
while(*p!='\0')
{
if(flag==0)
{
start.push_back(*p);
p++;
}

if(flag==1)
{
end.push_back(*p);
p++;
}

if(*p=='-')
{
p++;
flag=1;
}
if(*p==',')
{
if(end.size()==0)
perform(start,start,save);
else
perform(start,end,save);
p++;
start.clear();
end.clear();
flag=0;
}
}
if(end.size()==0)
perform(start,start,save);
else
perform(start,end,save);
}

void main()
{
string input;
cin>>input;
vector <int> save;//save是用来存储整数形式的值
ReadThrough(save,input);

int i;
for(i=0;i<save.size();i++) cout<<save[i]<<' ';cout<<endl;
vector <char> output;
intToChar(save,output);
i=0;
while(i<output.size())
{
cout<<output[i];
i++;
}
cout<<endl;

}