#pragma GCC optimize("O2,unroll-loops") #include <bits/stdc++.h> using namespace std; #define sz(x) (int)x.size() #define all(x) x.begin() , x.end() const int N = 131072; const int mod = 1e9 + 7; inline void ckadd(int &a , int b){ a += b; if(a >= mod)a -= mod; } struct Matrix{ int mat[4][4]; Matrix(){ memset(mat , 0 , sizeof(mat)); } friend Matrix mult(Matrix &a , Matrix &b){ Matrix c; for(int i = 0;i<4;i++){ for(int j = 0;j<4;j++){ for(int k = 0;k<4;k++){ ckadd(c.mat[i][j] , 1LL * a.mat[i][k] * b.mat[k][j] % mod); } } } return c; } void print(){ for(int i = 0;i<4;i++){ for(int j = 0;j<4;j++){ cout << mat[i][j] << " "; } cout << endl; } cout << endl; } } iden; vector < Matrix > t; Matrix merge(Matrix &x , Matrix &y){ return mult(x,y); } void init(){ t.assign(2*N , iden); } void update(int p, Matrix value) { // set value at position p for (t[p += N] = value; p >>= 1; ) t[p] = mult(t[p<<1], t[p<<1|1]); } Matrix query(int l, int r) { // sum on interval [l, r] Matrix resl = iden , resr = iden; for (r+=1 , l += N, r += N; l < r; l >>= 1, r >>= 1) { if (l&1) resl = mult(resl , t[l++]); if (r&1) resr = mult(t[--r] , resr); } return mult(resl , resr); } void solve(){ for(int i = 0;i<4;i++){ iden.mat[i][i] = 1; } init(); int n,q; cin >> n >> q; string str; cin >> str; auto upd = [&](int p , int x){// p yi x yap Matrix tran; tran.mat[0][0] = 8; tran.mat[0][1] = 1; tran.mat[0][2] = 1; tran.mat[0][3] = 0; tran.mat[1][0] = 8; tran.mat[1][1] = 1; tran.mat[1][2] = 0; tran.mat[1][3] = 0; tran.mat[2][0] = 8; tran.mat[2][1] = 1; tran.mat[2][2] = 1; tran.mat[2][3] = 0; tran.mat[3][0] = x; if(x > 3){ tran.mat[3][0] -= 2; } else if(x > 1){ tran.mat[3][0] -= 1; } if(x > 1){ tran.mat[3][1] = 1; } if((p == 0 or str[p-1] != '1') and x > 3){ tran.mat[3][2] = 1; } else{ tran.mat[3][2] = 0; } if(p > 0 and str[p-1] == '1' and x == 3){ tran.mat[3][3] = 0; } else{ tran.mat[3][3] = 1; } // cout << p << " tran : " << endl; // tran.print(); update(p , tran); }; auto que = [&](int l , int r){ Matrix st; int x = str[l] - '0'; st.mat[0][0] = x; if(x > 1){ st.mat[0][0]--; st.mat[0][1]++; } if(x > 3){ st.mat[0][0]--; st.mat[0][2]++; } st.mat[0][3] = 1; // cout << "st : " << endl; // st.print(); Matrix res = l == r ? iden : query(l+1 , r); st = mult(st , res); int ans = 0; for(int i = 0;i<4;i++){ ckadd(ans , st.mat[0][i]); } // cout << "res : " << endl; // st.print(); return ans; }; for(int i = 0;i<n;i++){ upd(i , str[i] - '0'); } cout << que(0,n-1) << endl; while(q--){ int typ; cin >> typ; if(typ == 1){ int l,r; cin >> l >> r; l-- , r--; cout << que(l,r) << endl; } else{ int p,x; cin >> p >> x; p--; upd(p , x); str[p] = '0' + x; } } } signed main(){ ios_base::sync_with_stdio(0);cin.tie(0); int testcase=1;//cin >> testcase; while(testcase--)solve(); cerr << 1000.0 * clock() / CLOCKS_PER_SEC << " ms" << endl; }