Leetcode 377. Combination Sum Ⅳ (DAY 46) ---- Dynamic programming learning period (Sooner or later when the pigeon goes down, it will become sfw, and it will not waste time to do problems every day)

Original title

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Code implementation (first brush small part to see the solution and most of the self-solving)

int combinationSum4(int* nums, int numsSize, int target){
    
    
    unsigned long* dp = (unsigned long*)malloc(sizeof(unsigned long) * (target+1));
    int i,j;
    memset(dp,0,sizeof(unsigned long) * (target+1));
    dp[0] = 1;
    for(i=1;i<=target;i++)
    {
    
    
        for(j=0;j<numsSize;j++)
        {
    
    
            if(i >= nums[j])
                dp[i] += dp[i-nums[j]];
        }
    }
    return dp[target];
}