atoi can do that for you
Example:
char string[] = “1234”;
int sum = atoi( string );
printf(“Sum = %dn”, sum ); // Outputs: Sum = 1234
Use atoi() from
http://linux.die.net/man/3/atoi
Or, write your own atoi() function which will convert char* to int
int a2i(const char *s)
{
int sign=1;
if(*s == ‘-‘){
sign = -1;
s++;
}
int num=0;
while(*s){
num=((*s)-‘0’)+num*10;
s++;
}
return num*sign;
}