#include <stdio.h>
int main(void) {
int a[] = {1,2,3,4,5,6};
int k = 2;
int vitri = 100;
for (int i=0;i<6;i++)
if (a[i]==k)
vitri = i;
if (vitri == 100)
else printf("tim thay tai %d", vitri
);
return 0;
}
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