/// @author Huy
/// @since 17:38:34 27/11/2025
#include <bits/stdc++.h>
#include <vector>
#include <cassert>
#ifndef CP_DS_QUERY_SEGMENT_TREE
#define CP_DS_QUERY_SEGMENT_TREE
namespace cp {
namespace ds {
template <typename Tp>
class segment_tree {
public:
using value_type = Tp;
segment_tree() : n(0), size(0) {}
segment_tree(int n, const value_type& val = value_type()) {
init(n, val);
}
segment_tree(const std::vector<value_type>& data) {
init(data);
}
void init(int n, const value_type& val = value_type()) {
std::vector<value_type> data(n, val);
init(data);
}
void init(const std::vector<value_type>& data) {
n = static_cast<int>(data.size());
for (size = 1; size < n; size <<= 1);
tree.assign(2 * size, value_type());
for (int i = 0; i < n; ++i) tree[size + i] = data[i];
for (int i = size - 1; i > 0; --i) pull(i);
}
void modify(int p, const value_type& val) {
assert(0 <= p && p < n);
p += size;
tree[p] = val;
for (p >>= 1; p > 0; p >>= 1) pull(p);
}
value_type point_query(int p) const {
assert(0 <= p && p < n);
return tree[p + size];
}
value_type range_query(int l, int r) const {
assert(0 <= l && l <= r && r <= n);
value_type sml = value_type();
value_type smr = value_type();
l += size;
r += size;
while (l < r) {
if (l & 1) sml = sml + tree[l++];
if (r & 1) smr = tree[--r] + smr;
l >>= 1;
r >>= 1;
}
return sml + smr;
}
value_type all_query() const {
return tree[1];
}
template <typename F>
int max_right(int l, F&& pred) const {
assert(0 <= l && l <= n);
if (l == n) return n;
value_type sm = value_type();
l += size;
do {
while ((l & 1) == 0) l >>= 1;
if (!pred(sm + tree[l])) {
while (l < size) {
l <<= 1;
if (pred(sm + tree[l])) sm = sm + tree[l++];
}
return l - size;
}
sm = sm + tree[l++];
} while ((l & -l) != l);
return n;
}
template <typename F>
int min_left(int r, F&& pred) const {
assert(0 <= r && r <= n);
if (r == 0) return 0;
value_type sm = value_type();
r += size;
do {
--r;
while (r > 1 && (r & 1)) r >>= 1;
if (!pred(tree[r] + sm)) {
while (r < size) {
r = (r << 1) | 1;
if (pred(tree[r] + sm)) sm = tree[r--] + sm;
}
return r + 1 - size;
}
sm = tree[r] + sm;
} while ((r & -r) != r);
return 0;
}
private:
int n, size;
std::vector<value_type> tree;
void pull(int i) {
tree[i] = tree[i << 1] + tree[(i << 1) | 1];
}
};
} // namespace ds
} // namespace cp
#endif
constexpr int inf = 2e9;
struct info {
int val = inf;
};
info operator+(const info& a, const info& b) {
return {std::min(a.val, b.val)};
}
signed main() {
std::ios_base::sync_with_stdio(false);
std::cin.tie(nullptr);
std::cout.tie(nullptr);
int n, q;
std::cin >> n >> q;
cp::ds::segment_tree<info> seg(n);
while (q--) {
char tp;
std::cin >> tp;
if (tp == 'M') {
int x, a;
std::cin >> x >> a;
seg.modify(a - 1, {x});
} else {
int y, b;
std::cin >> y >> b;
auto pred = [&](const info& node) {
return node.val > y;
};
int i = seg.max_right(b - 1, pred);
if (i == n) {
std::cout << "-1\n";
} else {
std::cout << i + 1 << '\n';
}
}
}
return 0;
}
