func_code_string: #include <bits/stdc++.h>   using namespace std;   template <typename T>   inline void read(T &x) {     x = 0;     int f = 1;     char ch = getchar();     for (; !isdigit(ch); ch = getchar())       if (ch ==  - ) f = -1;     for (; isdigit(ch); ch = getchar()) x = (x << 1) + (x << 3) + ch -  0 ;     x *= f;   }   int t, n;   const int maxn = 1e5 + 10;   int a[maxn];   map<int, bool> taked;   int main() {     read(t);     while (t--) {       bool flag = true;       taked.clear();       read(n);       int cnt = 0;       for (register int i = 0; i < n; i++) {         read(a[i]);         int c = ((a[i] + cnt) % n + n) % n;         if (taked[c]) flag = false;         taked[c] = true;         cnt++;       }       if (flag)         printf( YES n );       else         printf( NO n );     }     return 0;   }   