力扣2845.统计趣味子数组的数目
力扣2845.统计趣味子数组的数目
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同余
- 每次都写成ans += mp[s%mod]，下意识认为余数相等
- 应该是ans += mp[(s-k+modulo)%modulo];
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class Solution {public:long long countInterestingSubarrays(vector<int>& nums, int modulo, int k) {int n = nums.size();long long s = 0,ans = 0;unordered_map<int,int> mp;mp[0] = 1;for(int i=0;i<n;i++){s += (nums[i]%modulo == k);ans += mp[(s-k+modulo)%modulo];mp[s%modulo] ++;}return ans;}};