C++ program to compare two string

#include<iostream>
#include<conio.h>
#include<stdio.h>
#include<string.h>
#include<process.h>


int strcom(char*, char*);

int main()
{
    system("cls");
    char s1[100],s2[100];
    int f;

    std::cout<<"Enter the first string = ";
    gets(s1);
    std::cout<<"Enter the second string = ";
    gets(s2);

    f = strcom(s1,s2);

    std::cout<<f;

    getch();
}

int strcom(char *str1, char *str2)
{
    int i;
    int m = 0;
    int n = 0;

    for(i=0;i<strlen(str1); i++)
    {
        if(str1[i] == str2[i])
            m = m+1;
        if(m==strlen(str1))
        {
            std::cout<<"Both string are equal"<<std::endl;
            return(0);
            exit(0);
        }
    }

    for(i=0;i<strlen(str1);i++)
    {
        n = ((str1[i] - str2[i]));

        if(n<0)
        {
            std::cout<<"String one first "<<std::endl;
            return(-1);
            exit(0);
        }
        else if(n>0)
        {
            std::cout<<"String two first"<<std::endl;
            return(1);
            exit(0);
        }
    }
    return 0;
}

Enter the first string = this is a string
Enter the second string = this is a string
Both string are equal