#include <stdio.h>
#include <stdlib.h>
#include <string.h>
 
void cleanup(char *string1, char *string2, int pos) {
    memmove(&string1[pos], &string1[pos + strlen(string2)], strlen(string1)+1 - strlen(string2));
 
}
 
int main()
{
    char string1[100] = "holidayhousedayhouse";
    char string2[100] = "day";
 
 
 
    while(strstr(string1, string2)){
    	char *p = strstr(string1, string2);
            cleanup(string1, string2, p - string1);
    }
 
    printf("%s\n", string1);
    return 0;
}

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