# 1221.split-a-string-in-balanced-strings

## Statement

• Difficulty: Easy
• Tag: `贪心` `字符串` `计数`

``````输入：s = "RLRRLLRLRL"

``````

``````输入：s = "RLLLLRRRLR"

``````

``````输入：s = "LLLLRRRR"

``````

``````输入：s = "RLRRRLLRLL"

``````

• `1 <= s.length <= 1000`
• `s[i] = 'L' 或 'R'`
• `s` 是一个 平衡 字符串

Balanced strings are those that have an equal quantity of `'L'` and `'R'` characters.

Given a balanced string `s`, split it in the maximum amount of balanced strings.

Return the maximum amount of split balanced strings.

Example 1:

``````Input: s = "RLRRLLRLRL"
Output: 4
Explanation: s can be split into "RL", "RRLL", "RL", "RL", each substring contains same number of 'L' and 'R'.
``````

Example 2:

``````Input: s = "RLLLLRRRLR"
Output: 3
Explanation: s can be split into "RL", "LLLRRR", "LR", each substring contains same number of 'L' and 'R'.
``````

Example 3:

``````Input: s = "LLLLRRRR"
Output: 1
Explanation: s can be split into "LLLLRRRR".
``````

Constraints:

• `1 <= s.length <= 1000`
• `s[i]` is either `'L'` or `'R'`.
• `s` is a balanced string.

## Solution

``````#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>

#define endl "\n"
#define fi first
#define se second
#define all(x) begin(x), end(x)
#define rall rbegin(a), rend(a)
#define bitcnt(x) (__builtin_popcountll(x))
#define complete_unique(a) a.erase(unique(begin(a), end(a)), end(a))
#define mst(x, a) memset(x, a, sizeof(x))
#define MP make_pair

using ll = long long;
using ull = unsigned long long;
using db = double;
using ld = long double;
using VLL = std::vector<ll>;
using VI = std::vector<int>;
using PII = std::pair<int, int>;
using PLL = std::pair<ll, ll>;

using namespace __gnu_pbds;
using namespace std;
template <typename T>
using ordered_set = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
const ll mod = 1e9 + 7;

template <typename T, typename S>
inline bool chmax(T &a, const S &b) {
return a < b ? a = b, 1 : 0;
}

template <typename T, typename S>
inline bool chmin(T &a, const S &b) {
return a > b ? a = b, 1 : 0;
}

#ifdef LOCAL
#include <debug.hpp>
#else
#define dbg(...)
#endif

class Solution {
public:
int balancedStringSplit(string s) {
int res = 0;
auto f = vector<int>(2, 0);
for (const auto &c : s) {
int cur = (c == 'L');
if (f[cur ^ 1]) {
--f[cur ^ 1];
} else {
++f[cur];
}

if (f[0] == 0 && f[1] == 0) {
++res;
}
}

return res;
}
};

#ifdef LOCAL

int main() {
return 0;
}

#endif
``````