Convert Char to Int help!

hi,

Use the atoi() or atol() function, wich convert an string to an integer or long respectively.

#include <stdlib.h>

int value = atoi(time);

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Hi, I write few function to convert std::string to int

#include "iostream"
#include "string.h"

using namespace std;

int charToint(char ch)
{
	switch(ch)
	{
		case '0':	return 0;
		case '1':	return 1;
		case '2':	return 2;
		case '3':	return 3;
		case '4':	return 4;
		case '5':	return 5;
		case '6':	return 6;
		case '7':	return 7;
		case '8':	return 8;
		case '9':	return 9;		
	};
}
int pow(int n)
{
	int i = 0;
	int r = 1;
	while(i<n)
	{
		r *= 10;
		i++;
	}
	return r;
}
int atoi(string strNumber)
{
	if (strNumber.length() == 0) return 0;
	int i=0, j=0;
	int number = 0;
	for (i=0;i<strNumber.length();i++)
	{
		number += charToint((char)strNumber[i]) * pow(strNumber.length()-j-1);
		j++; 
	}
	return number;
}

int main(int argc, char const *argv[])
{
	string strNumber;
	getline(cin, strNumber);
	cout<<atoi(strNumber)<<endl;
	return 0;
}

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@Phạm Minh Toàn:
I don't see the point in re-doing the wheel ....

@
magdiel linhares:
I didn't notice this was C++, in that case, scratch my previous answer and use the std::stoi() function (defined in the string header).

Also, since you're coding in C++, use string objects instead of those horrible C-Style arrays, and use teh std::cout object to print you datas to the standard output instead of printf.

Last, using the "using namespace std" directive is considered a bad practice. It's sole porpose is to ensure compatibility with older code base when namespaces were introduced in C++ (back in 1990), it have no business in modern codes.
Either fully qualify your function calls, or select precisely what you need:

int main()
{
    std::cout << "Hello world." << std::endl;
    return 0;
}

int main()
{
    using std::cout;
    using std::endl;

    cout << "Hello world." << endl;
    return 0;
}

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@Fabrice Lambert, you're right. Thanks

Thanks! Working :3