/+ dub.sdl:
    name "A"
    dependency "dcomp" version=">=0.6.0"
+/

import std.stdio, std.algorithm, std.range, std.conv;
import std.typecons;
import std.bigint;

// import dcomp.foundation, dcomp.scanner;

int main() {
    auto sc = new Scanner(stdin);
    long n, m;
    sc.read(n, m);
    long[][] a = new long[][](n, m);
    foreach (i; 0..n) {
        sc.read(a[i]);
        if (i && a[i-1][0] > a[i][0]) {
            writeln(-1);
            return 0;
        }
    }
    if (m == 1) {
        foreach (i; 1..n) {
            if (a[i-1][0] == a[i][0]) {
                writeln(-1);
                return 0;
            }
        }
        writeln(0);
        return 0;
    }
    // m >= 2
    immutable INF = 10L^^9 + 10L^^7;
    long[][] C = new long[][](2020, 2020);
    C[0][0] = 1;
    foreach (i; 1..2020) {
        C[i][0] = C[i-1][0];
        foreach (j; 1..2020) {
            C[i][j] = min(INF, C[i-1][j-1] + C[i-1][j]);
        }
    }
    long[] suc(long[] x, long c) {
        long[] y = x.dup;
        if (c == 0) return y;

        foreach (i; 1..m) {
            foreach (j; 0..i) {
                long di = i-j;
                long fr;
                if (di < 6) {
                    fr = 1;
                    double u = 1;
                    foreach (k; 0..di) {
                        fr *= c-1+di-k;
                        u *= c-1+di-k;
                        fr /= k+1;
                        u /= k+1;
                    }
                    if (u > 1e10) fr = INF;
                } else {
                    fr = C[c-1+di][di];
                }
                y[i] += x[j] * fr;
                y[i] = min(y[i], INF);
            }
            if (y[i] == INF) break;
        }
        return y;
    }
    long[] co = new long[n];
    foreach (i; 1..n) {
        if (a[i-1][0] < a[i][0]) {
            continue;
        }
        // a[i-1][0] == a[i][0]
        long b2 = a[i-1][1] + a[i-1][0] * co[i-1];
        if (b2 < a[i][1]) {
            continue;
        }
        long c = b2 - a[i][1];
        if (c % a[i][0]) {
            co[i] = c / a[i][0] + 1;
            continue;
        }
        co[i] = c / a[i][0];
        long mi = min(co[i-1], co[i]);
        long[] x1 = suc(a[i-1], co[i-1]-mi);
        long[] x2 = suc(a[i], co[i]-mi);
        if (cmp(x1, x2) != -1) {
            co[i]++;
        }
    }
    writeln(co.sum);
    return 0;
}
/* IMPORT /home/yosupo/Program/dcomp/source/dcomp/foundation.d */
// module dcomp.foundation;
//fold(for old compiler)
static if (__VERSION__ <= 2070) {
    template fold(fun...) if (fun.length >= 1) {
        auto fold(R, S...)(R r, S seed) {
            import std.algorithm : reduce;
            static if (S.length < 2) {
                return reduce!fun(seed, r);
            } else {
                import std.typecons : tuple;
                return reduce!fun(tuple(seed), r);
            }
        }
    }
    unittest {
        import std.stdio;
        auto l = [1, 2, 3, 4, 5];
        assert(l.fold!"a+b"(10) == 25);
    }
}
version (X86) static if (__VERSION__ < 2071) {
    int bsf(ulong v) {
        foreach (i; 0..64) {
            if (v & (1UL << i)) return i;
        }
        return -1;
    }
    int bsr(ulong v) {
        foreach_reverse (i; 0..64) {
            if (v & (1UL << i)) return i;
        }
        return -1;   
    }
    int popcnt(ulong v) {
        int c = 0;
        foreach (i; 0..64) {
            if (v & (1UL << i)) c++;
        }
        return c;
    }
}
/* IMPORT /home/yosupo/Program/dcomp/source/dcomp/scanner.d */
// module dcomp.scanner;

class Scanner {
    import std.stdio : File;
    import std.conv : to;
    import std.range : front, popFront, array, ElementType;
    import std.array : split;
    import std.traits : isSomeChar, isStaticArray, isArray; 
    import std.algorithm : map;
    File f;
    this(File f) {
        this.f = f;
    }
    char[512] lineBuf;
    char[] line;
    private bool succ() {
        import std.range.primitives : empty, front, popFront;
        import std.ascii : isWhite;
        while (true) {
            while (!line.empty && line.front.isWhite) {
                line.popFront;
            }
            if (!line.empty) break;
            if (f.eof) return false;
            line = lineBuf[];
            f.readln(line);
        }
        return true;
    }

    private bool readSingle(T)(ref T x) {
        import std.algorithm : findSplitBefore;
        import std.string : strip;
        import std.conv : parse;
        if (!succ()) return false;
        static if (isArray!T) {
            alias E = ElementType!T;
            static if (isSomeChar!E) {
                //string or char[10] etc
                //todo optimize
                auto r = line.findSplitBefore(" ");
                x = r[0].strip.dup;
                line = r[1];
            } else {
                auto buf = line.split.map!(to!E).array;
                static if (isStaticArray!T) {
                    //static
                    assert(buf.length == T.length);
                }
                x = buf;
                line.length = 0;
            }
        } else {
            x = line.parse!T;
        }
        return true;
    }
    int read(T, Args...)(ref T x, auto ref Args args) {
        if (!readSingle(x)) return 0;
        static if (args.length == 0) {
            return 1;
        } else {
            return 1 + read(args);
        }
    }
}



unittest {
    import std.path : buildPath;
    import std.file : tempDir;
    import std.algorithm : equal;
    import std.stdio : File;
    string fileName = buildPath(tempDir, "kyuridenanmaida.txt");
    auto fout = File(fileName, "w");
    fout.writeln("1 2 3");
    fout.writeln("ab cde");
    fout.writeln("1.0 1.0 2.0");
    fout.close;
    Scanner sc = new Scanner(File(fileName, "r"));
    int a;
    int[2] b;
    char[2] c;
    string d;
    double e;
    double[] f;
    sc.read(a, b, c, d, e, f);
    assert(a == 1);
    assert(equal(b[], [2, 3]));
    assert(equal(c[], "ab"));
    assert(equal(d, "cde"));
    assert(e == 1.0);
    assert(equal(f, [1.0, 2.0]));
}

unittest {
    import std.path : buildPath;
    import std.file : tempDir;
    import std.algorithm : equal;
    import std.stdio : File, writeln;
    import std.datetime;
    string fileName = buildPath(tempDir, "kyuridenanmaida.txt");
    auto fout = File(fileName, "w");
    foreach (i; 0..1_000_000) {
        fout.writeln(3*i, " ", 3*i+1, " ", 3*i+2);
    }
    fout.close;
    writeln("Scanner Speed Test(3*1,000,000 int)");
    StopWatch sw;
    sw.start;
    Scanner sc = new Scanner(File(fileName, "r"));
    foreach (i; 0..500_000) {
        int a, b, c;
        sc.read(a, b, c);
        assert(a == 3*i);
        assert(b == 3*i+1);
        assert(c == 3*i+2);
    }
    foreach (i; 500_000..700_000) {
        int[3] d;
        sc.read(d);
        int a = d[0], b = d[1], c = d[2];
        assert(a == 3*i);
        assert(b == 3*i+1);
        assert(c == 3*i+2);
    }
    foreach (i; 700_000..1_000_000) {
        int[] d;
        sc.read(d);
        assert(d.length == 3);
        int a = d[0], b = d[1], c = d[2];
        assert(a == 3*i);
        assert(b == 3*i+1);
        assert(c == 3*i+2);
    }
    writeln(sw.peek.msecs, "ms");
}


Measured memory_bytes: 61436