import std.conv, std.functional, std.stdio, std.string; import std.algorithm, std.array, std.bigint, std.container, std.math, std.numeric, std.range, std.regex, std.typecons; import core.bitop; class EOFException : Throwable { this() { super("EOF"); } } string[] tokens; string readToken() { for (; tokens.empty; ) { if (stdin.eof) { throw new EOFException; } tokens = readln.split; } auto token = tokens.front; tokens.popFront; return token; } int readInt() { return readToken.to!int; } long readLong() { return readToken.to!long; } real readReal() { return readToken.to!real; } bool chmin(T)(ref T t, in T f) { if (t > f) { t = f; return true; } else { return false; } } bool chmax(T)(ref T t, in T f) { if (t < f) { t = f; return true; } else { return false; } } int binarySearch(alias pred, T)(in T[] as) { int lo = -1, hi = cast(int)(as.length); for (; lo + 1 < hi; ) { const mid = (lo + hi) >> 1; (unaryFun!pred(as[mid]) ? hi : lo) = mid; } return hi; } int lowerBound(T)(in T[] as, T val) { return as.binarySearch!(a => (a >= val)); } int upperBound(T)(in T[] as, T val) { return as.binarySearch!(a => (a > val)); } int N, M; int[] A, B, C; void main() { try { for (; ; ) { N = readInt(); M = readInt(); A = new int[M]; B = new int[M]; C = new int[M]; foreach (i; 0 .. M) { A[i] = readInt(); B[i] = readInt(); C[i] = readInt(); } auto score = new int[][](1 << N, N); foreach (p; 0 .. 1 << N) { foreach (u; 0 .. N) { foreach (i; 0 .. M) { if (((p >> A[i]) & 1) && (u == B[i])) { score[p][u] += C[i]; } } } } auto dp = new int[1 << N]; foreach (p; 0 .. 1 << N) { foreach (u; 0 .. N) { if (!((p >> u) & 1)) { chmax(dp[p | 1 << u], dp[p] + score[p][u]); } } } writeln(dp[$ - 1]); } } catch (EOFException e) { } }