220.cpp

#include <vector>
#include <cstdio>
#include <algorithm>
#include <cmath>

int solve1(int screenHeight, int mouseHeight, int scrollStep, int tableHeight, int linesCount, const std::vector<int> & linePos) {
    std::vector<int> count(screenHeight), countMod(scrollStep);

    // First screen
    int left = 0, right = linesCount-1;

    while (left < linesCount && linePos[left] < screenHeight) {
        for (int i = linePos[left]; i >= 0; i -= scrollStep) {
            ++count[i];
        }
        ++left;
    }

    // Last Screen
    // U-1 + k*T == L-1 --> k = [(L-U) / T]+1;
    int k = (int)ceil((tableHeight-screenHeight) * 1.0 / scrollStep);
    while (right > left && linePos[right] >= k*scrollStep) {
        for (int i = linePos[right]-k*scrollStep; i < screenHeight; i += scrollStep) {
            ++count[i];
        }
        --right;
    }

    // Mid screen
    for (int line_id = left; line_id <= right; ++line_id) {
        ++countMod[linePos[line_id] % scrollStep];
    }

    // Find best pos
    int min_sum = (int) 1e9;
    for (int startPos = 0; startPos+mouseHeight-1 < screenHeight; ++startPos) {
        int sum = 0;
        for (int i = startPos; i <= startPos+mouseHeight-1; ++i) {
            sum += count[i]+countMod[i % scrollStep];
        }
        min_sum = std::min(sum, min_sum);
    }

    return min_sum;
}

int main() {
    freopen("input.txt", "rt", stdin);

    int screenHeight, mouseHeight, scrollStep, tableHeight;
    scanf("%d %d %d %d", &screenHeight, &mouseHeight, &scrollStep, &tableHeight);

    int countLines;
    scanf("%d", &countLines);

    std::vector<int> linePos(countLines);

    for (auto & x : linePos)
        scanf("%d", &x);

    printf("%d", solve1(screenHeight, mouseHeight, scrollStep, tableHeight,countLines,linePos));

    return 0;
}