#include <stdio.h>
int main() {
    int n, a[], i, equal = 1;
    scanf("%d", &n);
    for (i = 0; i < n; i++) {
        scanf("%d", &a[n - 1]);
    }
    for (i = 0; i <= n - 1; i++) {
        if (a[0] != a[i]) {
            equal = 0;
            break;
        }
    }
    if (equal = 1)
        printf("Yes");
    else
        printf("No");
}

/sandbox/1/a.c:3:8: error: definition of variable with array type needs an explicit size or an initializer
{int n,a[],i,equal=1;
       ^
/sandbox/1/a.c:14:9: warning: using the result of an assignment as a condition without parentheses [-Wparentheses]
if(equal=1)
   ~~~~~^~
/sandbox/1/a.c:14:9: note: place parentheses around the assignment to silence this warning
if(equal=1)
        ^
   (      )
/sandbox/1/a.c:14:9: note: use '==' to turn this assignment into an equality comparison
if(equal=1)
        ^
        ==
1 warning and 1 error generated.