func_code_string: #pragma GCC optimize ( Ofast )   #include<bits/stdc++.h>   using namespace std;   void*wmem;   char memarr[96000000];   template<class T> inline void walloc1d(T **arr, int x, void **mem = &wmem){     static int skip[16] = {0, 15, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1};     (*mem) = (void*)( ((char*)(*mem)) + skip[((unsigned long long)(*mem)) & 15] );     (*arr)=(T*)(*mem);     (*mem)=((*arr)+x);   }   template<class T> inline void walloc1d(T **arr, int x1, int x2, void **mem = &wmem){     walloc1d(arr, x2-x1, mem);     (*arr) -= x1;   }   template<class T1> void sortA_L(int N, T1 a[], void *mem = wmem){     sort(a, a+N);   }   template<class T1, class T2> void sortA_L(int N, T1 a[], T2 b[], void *mem = wmem){     int i;     pair<T1, T2>*arr;     walloc1d(&arr, N, &mem);     for(i=(0);i<(N);i++){       arr[i].first = a[i];       arr[i].second = b[i];     }     sort(arr, arr+N);     for(i=(0);i<(N);i++){       a[i] = arr[i].first;       b[i] = arr[i].second;     }   }   inline int my_getchar(){     static char buf[1048576];     static int s = 1048576;     static int e = 1048576;     if(s == e && e == 1048576){       e = fread(buf, 1, 1048576, stdin);       s = 0;     }     if(s == e){       return EOF;     }     return buf[s++];   }   inline void rd(int &x){     int k;     int m=0;     x=0;     for(;;){       k = my_getchar();       if(k== - ){         m=1;         break;       }       if( 0 <=k&&k<= 9 ){         x=k- 0 ;         break;       }     }     for(;;){       k = my_getchar();       if(k< 0 ||k> 9 ){         break;       }       x=x*10+k- 0 ;     }     if(m){       x=-x;     }   }   inline int rd_int(void){     int x;     rd(x);     return x;   }   struct MY_WRITER{     char buf[1048576];     int s;     int e;     MY_WRITER(){       s = 0;       e = 1048576;     }     ~MY_WRITER(){       if(s){         fwrite(buf, 1, s, stdout);       }     }   }   ;   MY_WRITER MY_WRITER_VAR;   void my_putchar(int a){     if(MY_WRITER_VAR.s == MY_WRITER_VAR.e){       fwrite(MY_WRITER_VAR.buf, 1, MY_WRITER_VAR.s, stdout);       MY_WRITER_VAR.s = 0;     }     MY_WRITER_VAR.buf[MY_WRITER_VAR.s++] = a;   }   inline void wt_L(char a){     my_putchar(a);   }   inline void wt_L(int x){     int s=0;     int m=0;     char f[10];     if(x<0){       m=1;       x=-x;     }     while(x){       f[s++]=x%10;       x/=10;     }     if(!s){       f[s++]=0;     }     if(m){       my_putchar( - );     }     while(s--){       my_putchar(f[s]+ 0 );     }   }   template<class S, class T> inline S divup_L(S a, T b){     return (a+b-1)/b;   }   int M;   int K;   int A[200000];   int sz;   int arr[200000];   int ind[200000];   int n;   int res[1000][1000];   int main(){     int Lj4PdHRW;     wmem = memarr;     int KL2GvlyY = rd_int();     for(Lj4PdHRW=(0);Lj4PdHRW<(KL2GvlyY);Lj4PdHRW++){       int i;       rd(M);       rd(K);       {         int cTE1_r3A;         for(cTE1_r3A=(0);cTE1_r3A<(K);cTE1_r3A++){           rd(A[cTE1_r3A]);         }       }       for(i=(0);i<(K);i++){         ind[i] = i+1;       }       sortA_L(K, A, ind);       sz = n = 0;       for(i=(0);i<(K);i++){         int ao_dF3pO;         for(ao_dF3pO=(0);ao_dF3pO<(A[i]);ao_dF3pO++){           arr[sz++] = ind[i];         }       }       while( ((divup_L(n,2))) * n + (n/2) * ((divup_L(n,2))) < M ){         n++;       }       while( ((divup_L(n,2))) * n < A[K-1] ){         n++;       }       for(i=(0);i<(n);i++){         int j;         for(j=(0);j<(n);j++){           res[i][j] = 0;         }       }       for(i=(0);i<(n);i+=(2)){         int j;         for(j=(1);j<(n);j+=(2)){           if(sz > 0){             res[i][j] = arr[--sz];           }         }       }       for(i=(0);i<(n);i+=(2)){         int j;         for(j=(0);j<(n);j+=(2)){           if(sz > 0){             res[i][j] = arr[--sz];           }         }       }       for(i=(1);i<(n);i+=(2)){         int j;         for(j=(0);j<(n);j+=(2)){           if(sz > 0){             res[i][j] = arr[--sz];           }         }       }       wt_L(n);       wt_L(  n );       {         int szDqbNYU;         int ytthggxT;         for(szDqbNYU=(0);szDqbNYU<(n);szDqbNYU++){           if(n==0){             wt_L(  n );           }           else{             for(ytthggxT=(0);ytthggxT<(n-1);ytthggxT++){               wt_L(res[szDqbNYU][ytthggxT]);               wt_L(   );             }             wt_L(res[szDqbNYU][ytthggxT]);             wt_L(  n );           }         }       }     }     return 0;   }   // cLay version 20210502-1 [beta]      // --- original code ---   // //no-unlocked   // int M, K, A[2d5];   // int sz, arr[], ind[];   // int n, res[1000][1000];   // {   //   REP(rd_int()){   //     rd(M,K,A(K));   //    //     rep(i,K) ind[i] = i+1;   //     sortA(K, A, ind);   //    //     sz = n = 0;   //     rep(i,K) rep(A[i]) arr[sz++] = ind[i];   //    //     while( (n/+2) * n + (n/2) * (n/+2) < M ) n++;   //     while( (n/+2) * n < A[K-1] ) n++;   //    //     rep(i,n) rep(j,n) res[i][j] = 0;   //     rep(i,0,n,2) rep(j,1,n,2) if(sz > 0) res[i][j] = arr[--sz];   //     rep(i,0,n,2) rep(j,0,n,2) if(sz > 0) res[i][j] = arr[--sz];   //     rep(i,1,n,2) rep(j,0,n,2) if(sz > 0) res[i][j] = arr[--sz];   //    //     wt(n);   //     wt(res(n,n));   //   }   // }   