#include int main(void){ double X,Y; // Va,Vb [km/h] int N; // number of intersection int A[80]; // length of each intersection int i; // subscript double t; // time A arrive at A[i] scanf("%lf %lf %d",&X,&Y,&N); for(i = 0; i < N; i++){ scanf("%d",&A[i]); } // km/h -> m/s X /= 3.6; Y /= 3.6; for(i = 0; i < N - 1; i++){ t = (double)A[i] / X; if(Y * t > A[i+1]){ printf("NO\n"); return 0; } } printf("YES\n"); return 0; }