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							|  |  |  | id: 5900f4c81000cf542c50ffda | 
					
						
							|  |  |  | title: 'Problem 345: Matrix Sum' | 
					
						
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										 |  |  | challengeType: 5 | 
					
						
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										 |  |  | forumTopicId: 302004 | 
					
						
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										 |  |  | dashedName: problem-345-matrix-sum | 
					
						
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										 |  |  | # --description--
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										 |  |  | We define the Matrix Sum of a matrix as the maximum sum of matrix elements with each element being the only one in his row and column. | 
					
						
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										 |  |  | For example, the Matrix Sum of the matrix below equals $3315 ( = 863 + 383 + 343 + 959 + 767)$: | 
					
						
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							|  |  |  | $$\begin{array}{rrrrr} | 
					
						
							|  |  |  |     7                &  53                & 183                & 439                & \color{lime}{863} \\\\ | 
					
						
							|  |  |  |   497                & \color{lime}{383} & 563                &  79                & 973 \\\\ | 
					
						
							|  |  |  |   287                &  63                & \color{lime}{343} & 169                & 583 \\\\ | 
					
						
							|  |  |  |   627                & 343                & 773                & \color{lime}{959} & 943 \\\\ | 
					
						
							|  |  |  |   \color{lime}{767} & 473                & 103                & 699                & 303 | 
					
						
							|  |  |  | \end{array}$$ | 
					
						
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							|  |  |  | Find the Matrix Sum of: | 
					
						
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										 |  |  | $$\\begin{array}{r} | 
					
						
							|  |  |  |     7 &  53 & 183 & 439 & 863 & 497 & 383 & 563 &  79 & 973 & 287 &  63 & 343 & 169 & 583 \\\\ | 
					
						
							|  |  |  |   627 & 343 & 773 & 959 & 943 & 767 & 473 & 103 & 699 & 303 & 957 & 703 & 583 & 639 & 913 \\\\ | 
					
						
							|  |  |  |   447 & 283 & 463 &  29 &  23 & 487 & 463 & 993 & 119 & 883 & 327 & 493 & 423 & 159 & 743 \\\\ | 
					
						
							|  |  |  |   217 & 623 &   3 & 399 & 853 & 407 & 103 & 983 &  89 & 463 & 290 & 516 & 212 & 462 & 350 \\\\ | 
					
						
							|  |  |  |   960 & 376 & 682 & 962 & 300 & 780 & 486 & 502 & 912 & 800 & 250 & 346 & 172 & 812 & 350 \\\\ | 
					
						
							|  |  |  |   870 & 456 & 192 & 162 & 593 & 473 & 915 &  45 & 989 & 873 & 823 & 965 & 425 & 329 & 803 \\\\ | 
					
						
							|  |  |  |   973 & 965 & 905 & 919 & 133 & 673 & 665 & 235 & 509 & 613 & 673 & 815 & 165 & 992 & 326 \\\\ | 
					
						
							|  |  |  |   322 & 148 & 972 & 962 & 286 & 255 & 941 & 541 & 265 & 323 & 925 & 281 & 601 &  95 & 973 \\\\ | 
					
						
							|  |  |  |   445 & 721 &  11 & 525 & 473 &  65 & 511 & 164 & 138 & 672 &  18 & 428 & 154 & 448 & 848 \\\\ | 
					
						
							|  |  |  |   414 & 456 & 310 & 312 & 798 & 104 & 566 & 520 & 302 & 248 & 694 & 976 & 430 & 392 & 198 \\\\ | 
					
						
							|  |  |  |   184 & 829 & 373 & 181 & 631 & 101 & 969 & 613 & 840 & 740 & 778 & 458 & 284 & 760 & 390 \\\\ | 
					
						
							|  |  |  |   821 & 461 & 843 & 513 &  17 & 901 & 711 & 993 & 293 & 157 & 274 &  94 & 192 & 156 & 574 \\\\ | 
					
						
							|  |  |  |    34 & 124 &   4 & 878 & 450 & 476 & 712 & 914 & 838 & 669 & 875 & 299 & 823 & 329 & 699 \\\\ | 
					
						
							|  |  |  |   815 & 559 & 813 & 459 & 522 & 788 & 168 & 586 & 966 & 232 & 308 & 833 & 251 & 631 & 107 \\\\ | 
					
						
							|  |  |  |   813 & 883 & 451 & 509 & 615 &  77 & 281 & 613 & 459 & 205 & 380 & 274 & 302 &  35 & 805 | 
					
						
							|  |  |  | \end{array}$$ | 
					
						
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										 |  |  | # --hints--
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										 |  |  | `matrixSum()` should return `13938`. | 
					
						
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										 |  |  | ```js | 
					
						
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										 |  |  | assert.strictEqual(matrixSum(), 13938); | 
					
						
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										 |  |  | ``` | 
					
						
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										 |  |  | # --seed--
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										 |  |  | ## --seed-contents--
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							|  |  |  | ```js | 
					
						
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										 |  |  | function matrixSum() { | 
					
						
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										 |  |  |   return true; | 
					
						
							|  |  |  | } | 
					
						
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										 |  |  | matrixSum(); | 
					
						
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										 |  |  | ``` | 
					
						
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										 |  |  | # --solutions--
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							|  |  |  | ```js | 
					
						
							|  |  |  | // solution required | 
					
						
							|  |  |  | ``` |