class LazySegTree():
    #区間和のセグメント木、要素ls
    def __init__(self,ls):
        self.default = 0
        self.func = (lambda x, y: x + y)
        self.N = len(ls)
        self.K = (self.N-1).bit_length()
        self.N0 = 1 << self.K 
        self.dat = [self.default]*(2**(self.K+1))
        self.lazy = [0]*(2**(self.K+1)) #遅延評価
        for i in range(self.N): #葉の構築
            self.dat[2**self.K+i] = ls[i]
        self.build()

    def build(self):
        for j in range(self.N0-1,0,-1):
            self.dat[j] = self.func(self.dat[j<<1],self.dat[j<<1|1]) #親が持つ条件

    def leafvalue(self,x): #x番目の値を出力
        return self.query(x,x+1)

    def update_add(self,x,y): #x番目にyを足す
        return self.updatel_add(x,x+1,y)

    def gindex(self,l, r): #伝播するインデックス列挙
        L = l + self.N0; R = r + self.N0
        lm = (L // (L & -L)) >> 1
        rm = (R // (R & -R)) >> 1
        lsindex = []
        while L < R:
            if R <= rm:
                lsindex.append(R)
            if L <= lm:
                lsindex.append(L)
            L >>= 1; R >>= 1
        while L:
            lsindex.append(L)
            L >>= 1
        return lsindex

    def propagates(self,ids):
        for i in reversed(ids):
            v = self.lazy[i]
            if not v:
                continue
            self.lazy[i<<1] += v//2; self.lazy[i<<1|1] += v//2
            self.dat[i<<1] += v//2; self.dat[i<<1|1] += v//2
            self.lazy[i] = 0

    def updatel_add(self,l, r, x):#区間にyを足す
        self.propagates(self.gindex(l, r))
        L = self.N0 + l
        R = self.N0 + r
        ii = 0
        while L < R:
            if L & 1:
                self.lazy[L] += x*(2**ii)
                self.dat[L] += x*(2**ii)
                L += 1
            if R & 1:
                R -= 1
                self.lazy[R] += x*(2**ii)
                self.dat[R] += x*(2**ii)
            L >>= 1
            R >>= 1
            ii += 1
        for i in self.gindex(l, r):
            self.dat[i] = self.func(self.dat[i<<1],self.dat[i<<1|1])+self.lazy[i]

    def query(self,l, r):
        self.propagates(self.gindex(l, r))
        L = self.N0 + l
        R = self.N0 + r
        vL = self.default
        vR = self.default
        while L < R:
            if L & 1:
                vL = self.func(vL,self.dat[L])
                L += 1
            if R & 1:
                R -= 1
                vR = self.func(self.dat[R],vR)
            L >>= 1
            R >>= 1
        return self.func(vL,vR)

N,M = map(int,input().split())
ans = 0
LSG = LazySegTree([0]*(M))
lsab = []
for i in range(N):
    a,b = map(int, input().split())
    if a > b:
        a,b = b,a
    lsab.append((a,b))
lsab.sort()
for i in range(N):
    a,b = lsab[i]
    if b-a == 1:
        continue
    ans += abs(LSG.leafvalue(a)-LSG.leafvalue(b))
    LSG.updatel_add(a+1, b, 1)

print(ans)