Enter n in the first line (1<= n <= 500000). Next n lines per line, a number bi (1 <= bi <= 100000) represents the size of the i-th box
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Enter n in the first line (1<= n <= 500000). Next n lines per line, a number bi (1 <= bi <= 100000) represents the size of the i-th box
Output an integer indicating the minimum number of boxes that can be seen
5 1 5 4 9 3
3