Replace characters('., ') in a string with a special character('|').

Write a function to replace certain characters('., ') in a string with a special character('|').
Example,
Input => "Hey, I am a rockstar.....yeah"
Output => "Hey|I|am|a|rockstar|yeah"

Alternative:
Write an algo­rithm to replace all spaces in a given string with ‘%20′. You can consider that string has enough space at the end of the string to hold the extra characters.
http://algorithms.tutorialhorizon.com/replace-all-spaces-in-a-string-with/

Code:
#include<stdio.h>
#include<stdlib.h>
#include<string.h>

int hasCh(char *str, char ch)
{
    int len = strlen(str);
    int i = 0;

    for(i=0; i < len; i++)
    {
        if(str[i] == ch)
            return 1;
    }

    return 0;
}

void replace(char *str, char *delimit)
{
    int len = strlen(str);
    int cur = 0;
    int flag = 0;
    int i = 0;

    for(i=0; i< len; i++)
    {
        if(hasCh(delimit, str[i]))
        {
            if(!flag)
            {
                flag = 1;
                str[cur] = '|';
                cur++;
            }
        }
        else
        {
            flag = 0;
            str[cur] = str[i];
            cur++;
        }
    }

    str[cur] = '\0';
}

int main()
{
    char str[50] = {0, };

    sprintf(str, "%s", "Hey, I am a rockstart...yeah");

    replace(str, ", .");

    printf("%s\n", str);

    return 0;
}