when a problem says, memory limit : 256 MB. Does it stands for : every test case 256 MB or memory of sum of all testcases : 256 MB.

reason to ask : https://mirror.codeforces.com/contest/1472/submission/103587221

no way , i get MLE for test case 10 which has 121 vertices and 180 edges, while i passed 200000 vertices and 199999 edges case i.e test case 9 .

Any associated insight is much appreciated. Thanks in advance.