3 4
0 2000 1000 3000 0 3000
0 0 3000 0 3000 3000 0 3000
ans: 647.1067811865

5 6
0 2000 500 2500 1000 3000 1500 3000 0 3000
0 0 1500 0 3000 0 1500 0 3000 3000 0 3000
ans: 647.1067811865

3 4
0 0 4000 0 2000 4000
0 0 4000 0 4000 4000 0 4000
ans: 3517.7087639997

4 4
0 0 3000 0 3000 3000 0 3000
2000 2000 5000 2000 5000 5000 2000 5000
ans: 940

4 4
0 0 3000 0 3000 3000 0 3000
1000 1000 -2000 1000 -2000 -2000 1000 -2000
ans: 940

4 3
0 0 30000 0 30000 30000 0 30000
10000 40000 40000 10000 40000 40000
ans: 7011.0678118655

4 4
0 0 3000 0 3000 3000 0 3000
-1000 1000 5000 1000 5000 2000 -1000 2000
ans: 1940

4 4
0 0 3000 0 3000 3000 0 3000
-1000 2000 1000 -1000 2000 -1000 -1000 2000
ans: 647.1067811865

3 3
0 0 4000 2000 0 4000
3000 2000 7000 0 7000 4000
ans: 387.2135955000

Also, WA6 = integer overflow

What is algorithm? What formulas, theorems, equations and hints must I use?

what's wrong about my code ? Why it is wrong answer on test 5?

please, someone explain the test case. i don't get how it is 540.0