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  1. #include <bits/stdc++.h>
  2. #define ll long  long
  3. #define ld long double
  4. #define mod 1000000007
  5. #define max_char 128
  6. #define pb push_back
  7. #define ff first
  8. #define ss second
  9. #define mp make_pair
  10. #define lbd lower_bound
  11. #define ubd upper_bound
  12. #define PI 3.141592653589793238
  13. #define pf push_front
  14. #define all(x) x.begin(),x.end()
  15. #define input(arr,n) for(ll c1=0;c1<n;c1++)cin>>arr[c1];
  16. #define rep(i,a,n) for( ll i=a ; i<n ; i++)
  17. #define mems(x, y) memset(x, y, sizeof(x))
  18. #define fastio ios_base::sync_with_stdio(false);cin.tie(0);cout.tie(0);
  19. using namespace std;
  20. //cout<<"Case #"<<v1+1<<": ";
  21.  
  22. ll power(ll base,ll pow, ll mo)
  23. {
  24.    ll res=1;
  25.    while(pow)
  26.    {     
  27.         if (pow%2!=0)  res=(res*base)%mo;
  28.         base=(base*base)%mo;
  29.         pow/=2;
  30.    }
  31.    return res;
  32. }
  33.  
  34.  
  35. int main()
  36. {
  37.     fastio
  38. 	ll t,i,j,x;
  39. 	cin>>t;
  40. 	while(t--)
  41. 	{
  42. 	    int n,k;
  43. 	    cin>>n;
  44. 	    vector<int>a(n);
  45.  
  46. 	    for(i=0;i<n;i++)
  47. 	    cin>>a[i];
  48.  
  49. 	    vector<pair<ll,ll>>v;
  50. 	    for(i=0;i<n;i++)
  51. 	    {
  52. 	        v.pb(mp(a[i],i));
  53. 	    }
  54. 	    sort(all(v));
  55. 	    int f=1;
  56.  
  57. 	    int end=n-1;
  58. 	    int pos;
  59. 	    int vv=0;
  60. 	    for(i=0;i<n;i++)
  61. 	    {
  62. 	        pos=v[i].ss;
  63. 	        //cout<<pos<<" ";
  64. 	        if(vv==0&&pos==end)
  65. 	        {
  66. 	            --end;
  67. 	            vv=1;
  68. 	        }
  69. 	        else if(pos==end && end-v[i-1].ss==-1)
  70. 	        {
  71. 	            //cout<<"A";
  72. 	            f=0;
  73. 	            break;
  74. 	        }
  75. 	        else if(pos!=0 && vv==0 && a[pos]-a[pos-1]!=1)
  76. 	        {
  77. 	            f=0;
  78. 	            //cout<<i<<" ";
  79. 	            break;
  80. 	        }
  81.  
  82. 	        else{
  83. 	            vv=0;
  84. 	        }
  85. 	    }
  86.  
  87. 	    if(f)
  88. 	    cout<<"Yes";
  89. 	    else cout<<"No";
  90. 	    cout<<"\n";
  91. 	}
  92. 	return 0;
  93. }
Success #stdin #stdout 0s 4284KB
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stdin
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stdout
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Yes
Yes
No
https://ideone.com/6CAylm
language:
C++14 (gcc 8.3)
created:
4 years ago
visibility:
public

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