C++ program to check whether a sub string is present in a given string

Here is a C++ to check whether a sub string is present in a given string


 SOURCE CODE OUTPUT

#include<iostream>
#include<string.h>
using namespace std;
int main()
{
    char str[30],subst[20];
    int i,j=0;
    cout<<"Enter String : ";
    cin>>str;
    cout<<"Enter sub string : ";
    cin>>subst;
    for(i=0;str[i]!='\0';i++)
    {
        if(str[i]==subst[j])
            j++;
        else if(str[i]!=subst[j])
            j=0;
        if(subst[j]=='\0')
        {
            cout<<"Sub string is present";
            return 0;
        }
    }
    cout<<"Substring is not present ";
    return 0;
}

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