Cody

# Problem 1323. Alternating sum

Solution 2761447

Submitted on 30 Jul 2020
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### Test Suite

Test Status Code Input and Output
1   Pass
x=508; assert(isequal(altsum(x),508))

2   Fail
x=[1692 591]; assert(isequal(altsum(x),1101))

Error using ^ (line 51) Incorrect dimensions for raising a matrix to a power. Check that the matrix is square and the power is a scalar. To perform elementwise matrix powers, use '.^'. Error in altsum (line 3) y=sum(x .*(-1)^k); Error in Test2 (line 2) assert(isequal(altsum(x),1101))

3   Fail
x=[-644 380 1009]; assert(isequal(altsum(x),-15))

Error using ^ (line 51) Incorrect dimensions for raising a matrix to a power. Check that the matrix is square and the power is a scalar. To perform elementwise matrix powers, use '.^'. Error in altsum (line 3) y=sum(x .*(-1)^k); Error in Test3 (line 2) assert(isequal(altsum(x),-15))

4   Fail
x=[-20 -48 0 -318]; assert(isequal(altsum(x),346))

Error using ^ (line 51) Incorrect dimensions for raising a matrix to a power. Check that the matrix is square and the power is a scalar. To perform elementwise matrix powers, use '.^'. Error in altsum (line 3) y=sum(x .*(-1)^k); Error in Test4 (line 2) assert(isequal(altsum(x),346))

5   Fail
x=[1095 -1874 428 896 731 578 40]; assert(isequal(altsum(x),2694))

Error using ^ (line 51) Incorrect dimensions for raising a matrix to a power. Check that the matrix is square and the power is a scalar. To perform elementwise matrix powers, use '.^'. Error in altsum (line 3) y=sum(x .*(-1)^k); Error in Test5 (line 2) assert(isequal(altsum(x),2694))