字符串中的删除

//
//  main.c
//  assignment problem 1.2
//
//  Created by 毛遵杰 on 2019/9/29.
//  Copyright © 2019 毛遵杰. All rights reserved.
//

#include <stdio.h>


int del_substr(char *str,char const*substr)
{
    int i,j,k,flag,t;
    for (i=0;str[i] != '\0'; i++)
    {
        j=0;
        flag=0;
        if (str[i] == substr[j])
        {
            k=i;
            for (j=0; str[k] != '\0' && substr[j]!='\0'; k++,j++)
            {
                 if (str[k] != substr[j])
                 {
                     flag=1;
                     break;
                 }
            }
            if ( substr[j] =='\0' && flag == 0)
            {
                for (t=0;t<j;t++)
                {
                    for (k=i;str[k+1]!='\0';k++)
                    {
                        str[k]=str[k+1];
                    }
                    str[k]='\0';
                }
                str[k]='\0';
                return 1;
            }
        }
    }
    return 0;
}

int main()
{
    char s1[100]={0};//      "ABCDEFG"
    char s2[50]={0};

    while(1){

        printf("please enter string 1");
        scanf("%s",s1);
        printf(" please enter string 2");
        scanf("%s",s2);

        del_substr(s1,s2);
        printf("%s\n",s1);
    }
    

    

    return 0;
}