singingpigs.online
A little app to simulate every possible move in Connect Four.
Small make_move optimization
+26
-13
+26
-13
core.cpp
+26
-13
core.cpp
···
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{
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assert(column >= 0 && column < 7);
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-
uint8_t probe = 0b01000000;
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-
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if (state[column] >= probe)
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+
if (state[column] >= 0b01000000)
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return -1;
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int8_t row = 6;
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while (state[column] < probe)
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uint8_t mask = state[column]; // 0011 0000 (example)
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mask |= mask >> 1; // 0011 1000
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mask |= mask >> 2; // 0011 1110
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mask |= mask >> 4; // 0011 1111
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++mask; // 0100 0000
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+
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state[column] |= mask;
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if (player == 1)
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{
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-
probe >>= 1;
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--row;
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state[column] &= ~(mask >> 1);
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}
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if (player == 1)
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switch (mask)
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{
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state[column] &= ~(probe);
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case 0b00000010:
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return 0;
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case 0b00000100:
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return 1;
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case 0b00001000:
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return 2;
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case 0b00010000:
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return 3;
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case 0b00100000:
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return 4;
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case 0b01000000:
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return 5;
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default:
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assert(false);
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return -1;
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}
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-
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state[column] |= (probe << 1);
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-
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return row;
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}
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bool check_for_win(BoardState state, uint8_t last_move_row, uint8_t last_move_col)