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  1. #include <iostream>
  2. #include <cstdio>
  3. using namespace std;
  4.  
  5. int main() {
  6. 	int t, n, a[105], n_inv, l_inv;
  7. 	scanf("%d", &t);
  8. 	while(t--) {
  9. 		scanf("%d", &n);
  10. 		n_inv=l_inv=0;
  11. 		for(int i=0; i<n; i++) scanf("%d", &a[i]);
  12. 		for(int i=0; i<n-1; i++) for(int j=i+1; j<n; j++) if(a[i]>a[j]) n_inv++;
  13. 		for(int i=1; i<n; i++) if(a[i-1]>a[i]) l_inv++;
  14. 		if(l_inv==n_inv) printf("YES\n");
  15. 		else printf("NO\n");
  16. 	}
  17. 	return 0;
  18. }
Success #stdin #stdout 0s 3344KB
comments ()
stdin 
4
1
1
2
2 1
3
3 2 1
4
1 3 2 4
stdout 
YES
YES
NO
YES
https://ideone.com/zSwh4P
language:
C++ (gcc 8.3)
created:
11 years ago
visibility:
public

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