func_code_string: #include <bits/stdc++.h>   #pragma GCC optimize(3)   using namespace std;   const double PI = acos(-1.0);   const double eps = 1e-6;   inline int read() {     int x = 0, f = 1;     char ch = getchar();     while (ch <  0  || ch >  9 ) {       if (ch ==  - ) f = -1;       ch = getchar();     }     while (ch >=  0  && ch <=  9 ) {       x = x * 10 + ch -  0 ;       ch = getchar();     }     return x * f;   }   int a[200010];   int main() {     int n = read();     int fen = 0, gu = 0;     for (int i = 1; i <= n; i++) a[i] = read();     bool ok = 1;     for (int i = 2; i <= n; i++) {       if (a[i] == a[i - 1]) ok = 0;     }     if (ok == 0) {       printf( NO );       return 0;     }     for (int i = 2; i <= n - 1; i++) {       if (a[i - 1] < a[i] && a[i] > a[i + 1])         fen++;       else if (a[i - 1] > a[i] && a[i + 1] > a[i])         gu++;     }     if (fen <= 1 && gu == 0)       printf( YES );     else       printf( NO );     return 0;   }   