import sys
input = sys.stdin.readline

def I(): return int(input())
def MI(): return map(int, input().split())
def LI(): return list(map(int, input().split()))

def main():
    ###
    class LazySegmentTree:
        
        __slots__ = ["n", "data", "lazy", "me", "oe", "fmm", "fmo", "foo"]
    
        def __init__(self, monoid_data, monoid_identity, operator_identity, func_monoid_monoid, func_monoid_operator, func_operator_operator):
            self.me = monoid_identity
            self.oe = operator_identity
            self.fmm = func_monoid_monoid
            self.fmo = func_monoid_operator
            self.foo = func_operator_operator
    
            self.n = len(monoid_data)
            self.data = monoid_data * 2
            for i in range(self.n-1, 0, -1):
                self.data[i] = self.fmm(self.data[2*i], self.data[2*i+1])
            self.lazy = [self.oe] * (self.n * 2)
            
    
        def replace(self, index, value):
            index += self.n
    
            # propagation
            for shift in range(index.bit_length()-1, 0, -1):
                i = index >> shift
                self.lazy[2*i]   = self.foo(self.lazy[2*i],   self.lazy[i])
                self.lazy[2*i+1] = self.foo(self.lazy[2*i+1], self.lazy[i])
                self.data[i] = self.fmo(self.data[i], self.lazy[i])
                self.lazy[i] = self.oe
    
            # update
            self.data[index] = value
            self.lazy[index] = self.oe
    
            # recalculation
            i = index
            while i > 1:
                i //= 2
                self.data[i] = self.fmm( self.fmo(self.data[2*i], self.lazy[2*i]), self.fmo(self.data[2*i+1], self.lazy[2*i+1]) )
                self.lazy[i] = self.oe
    
    
        def effect(self, l, r, operator):
            l += self.n
            r += self.n
            
            # preparing indices
            indices = []
            l0 = (l // (l & -l))     // 2
            r0 = (r // (r & -r) - 1) // 2
            while r0 > l0:
                indices.append(r0)
                r0 //= 2
            while l0 > r0:
                indices.append(l0)
                l0 //= 2
            while l0 and l0 != r0:
                indices.append(r0)
                r0 //= 2
                if l0 == r0:
                    break
                indices.append(l0)
                l0 //= 2
            while r0:
                indices.append(r0)
                r0 //= 2
    
            # propagation
            for i in reversed(indices):
                self.lazy[2*i]   = self.foo(self.lazy[2*i],   self.lazy[i])
                self.lazy[2*i+1] = self.foo(self.lazy[2*i+1], self.lazy[i])
                self.data[i] = self.fmo(self.data[i], self.lazy[i])
                self.lazy[i] = self.oe
    
            # effect
            while l < r:
                if l % 2:
                    self.lazy[l] = self.foo(self.lazy[l], operator)
                    l += 1
                if r % 2:
                    r -= 1
                    self.lazy[r] = self.foo(self.lazy[r], operator)
                l //= 2
                r //= 2
    
            # recalculation
            for i in indices:
                self.data[i] = self.fmm( self.fmo(self.data[2*i], self.lazy[2*i]), self.fmo(self.data[2*i+1], self.lazy[2*i+1]) )
                self.lazy[i] = self.oe
                
            
        def folded(self, l, r):
            l += self.n
            r += self.n
    
            # preparing indices
            indices = []
            l0 = (l // (l & -l))     // 2
            r0 = (r // (r & -r) - 1) // 2
            while r0 > l0:
                indices.append(r0)
                r0 //= 2
            while l0 > r0:
                indices.append(l0)
                l0 //= 2
            while l0 and l0 != r0:
                indices.append(r0)
                r0 //= 2
                if l0 == r0:
                    break
                indices.append(l0)
                l0 //= 2
            while r0:
                indices.append(r0)
                r0 //= 2
            
            # propagation
            for i in reversed(indices):
                self.lazy[2*i]   = self.foo(self.lazy[2*i],   self.lazy[i])
                self.lazy[2*i+1] = self.foo(self.lazy[2*i+1], self.lazy[i])
                self.data[i] = self.fmo(self.data[i], self.lazy[i])
                self.lazy[i] = self.oe
    
            # fold
            left_folded = self.me
            right_folded = self.me
            while l < r:
                if l % 2:
                    left_folded = self.fmm(left_folded, self.fmo(self.data[l], self.lazy[l]))
                    l += 1
                if r % 2:
                    r -= 1
                    right_folded = self.fmm(self.fmo(self.data[r], self.lazy[r]), right_folded)
                l //= 2
                r //= 2
            return self.fmm(left_folded, right_folded)
        
    ####




    mod=10**9+7
    N,Q=MI()
    
    monoid_data=[N-1]*N
    def fmm(m1, m2):
        return min(m1,m2)
    def fmo(m1,o1):
        return min(m1,o1)
    def foo(o1,o2):
        return min(o1,o2)
    
    inf=10**6
    seg_row=LazySegmentTree(monoid_data, inf, inf, fmm, fmo, foo)#横向きに伸びる白のラインを管理，次の白は何列目？
    seg_col=LazySegmentTree(monoid_data, inf, inf, fmm, fmo, foo)
 
    bl=(N-2)*(N-2)
    
    for _ in range(Q):
        q,x=MI()
        x-=1
        if q==1:
            row=seg_row.folded(x,x+1)
            bl-=row-1
            seg_col.effect(0,row,x)
            
        else:
            col=seg_col.folded(x,x+1)
            bl-=col-1
            seg_row.effect(0,col,x)
            
    print(bl)
            
            

main()


Measured memory_bytes: 92060