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i can't find why the system refuse my code
i can't find where is the mistake
can you help me please?

here is my code:

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#define SIZE 10
void sum(char x[SIZE],long *sum) {
int i;
for(i=0; i<SIZE; i++)
*sum+=x ;
}
int main() {
char x[SIZE ...